SPI chaining with TMCStepper simplified interface (#15179)

Marlin/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

Marlin/src/feature/tmc_util.h

     TMCMarlin(const uint16_t cs_pin, const float RS) :
       TMC(cs_pin, RS)
       {}
+    TMCMarlin(const uint16_t cs_pin, const float RS, const uint8_t axis_chain_index) :
+      TMC(cs_pin, RS, axis_chain_index)
+      {}
     TMCMarlin(const uint16_t CS, const float RS, const uint16_t pinMOSI, const uint16_t pinMISO, const uint16_t pinSCK) :
       TMC(CS, RS, pinMOSI, pinMISO, pinSCK)
       {}
+    TMCMarlin(const uint16_t CS, const float RS, const uint16_t pinMOSI, const uint16_t pinMISO, const uint16_t pinSCK, const uint8_t axis_chain_index) :
+      TMC(CS, RS, pinMOSI, pinMISO, pinSCK,  axis_chain_index)
+      {}
     inline uint16_t rms_current() { return TMC::rms_current(); }
     inline void rms_current(uint16_t mA) {
       this->val_mA = mA;
 template<char AXIS_LETTER, char DRIVER_ID, AxisEnum AXIS_ID>
 class TMCMarlin<TMC2660Stepper, AXIS_LETTER, DRIVER_ID, AXIS_ID> : public TMC2660Stepper, public TMCStorage<AXIS_LETTER, DRIVER_ID> {
   public:
-    TMCMarlin(const uint16_t cs_pin, const float RS) :
+    TMCMarlin(const uint16_t cs_pin, const float RS, const uint8_t) :
       TMC2660Stepper(cs_pin, RS)
       {}
-    TMCMarlin(const uint16_t CS, const float RS, const uint16_t pinMOSI, const uint16_t pinMISO, const uint16_t pinSCK) :
+    TMCMarlin(const uint16_t CS, const float RS, const uint16_t pinMOSI, const uint16_t pinMISO, const uint16_t pinSCK, const uint8_t) :
       TMC2660Stepper(CS, RS, pinMOSI, pinMISO, pinSCK)
       {}
     inline uint16_t rms_current() { return TMC2660Stepper::rms_current(); }

Marlin/src/inc/Conditionals_adv.h

 // Extensible UI pin mapping for RepRapDiscount
 #define TOUCH_UI_ULTIPANEL ENABLED(LULZBOT_TOUCH_UI) && ANY(AO_EXP1_PINMAP, AO_EXP2_PINMAP, CR10_TFT_PINMAP)
 
-// TMC SPI Chaining
-#define TMC_USE_CHAIN (X_CHAIN_POS||Y_CHAIN_POS||Z_CHAIN_POS||X2_CHAIN_POS||Y2_CHAIN_POS||Z2_CHAIN_POS||Z3_CHAIN_POS||E0_CHAIN_POS||E1_CHAIN_POS||E2_CHAIN_POS||E3_CHAIN_POS||E4_CHAIN_POS||E5_CHAIN_POS)
-
 // Poll-based jogging for joystick and other devices
 #if ENABLED(JOYSTICK)
   #define POLL_JOG

Marlin/src/inc/SanityCheck.h

   #error "STEALTHCHOP requires TMC2130, TMC2160, TMC2208, TMC2209, or TMC5160 stepper drivers."
 #endif
 
-#if TMC_USE_CHAIN
-  #if  (X_CHAIN_POS  && !PIN_EXISTS(X_CS) ) \
-    || (Y_CHAIN_POS  && !PIN_EXISTS(Y_CS) ) \
-    || (Z_CHAIN_POS  && !PIN_EXISTS(Z_CS) ) \
-    || (X2_CHAIN_POS && !PIN_EXISTS(X2_CS)) \
-    || (Y2_CHAIN_POS && !PIN_EXISTS(Y2_CS)) \
-    || (Z2_CHAIN_POS && !PIN_EXISTS(Z2_CS)) \
-    || (Z3_CHAIN_POS && !PIN_EXISTS(Z3_CS)) \
-    || (E0_CHAIN_POS && !PIN_EXISTS(E0_CS)) \
-    || (E1_CHAIN_POS && !PIN_EXISTS(E1_CS)) \
-    || (E2_CHAIN_POS && !PIN_EXISTS(E2_CS)) \
-    || (E3_CHAIN_POS && !PIN_EXISTS(E3_CS)) \
-    || (E4_CHAIN_POS && !PIN_EXISTS(E4_CS)) \
-    || (E5_CHAIN_POS && !PIN_EXISTS(E5_CS))
-    #error "With TMC_USE_CHAIN all chained TMC drivers need a CS pin."
+#define IN_CHAIN(A) (A##_CHAIN_POS > 0)
+// TMC SPI Chaining
+#if IN_CHAIN(X) || IN_CHAIN(Y) || IN_CHAIN(Z) || IN_CHAIN(X2) || IN_CHAIN(Y2) || IN_CHAIN(Z2) || IN_CHAIN(Z3) || IN_CHAIN(E0) || IN_CHAIN(E1) || IN_CHAIN(E2) || IN_CHAIN(E3) || IN_CHAIN(E4) || IN_CHAIN(E5)
+  #if  (IN_CHAIN(X)  && !PIN_EXISTS(X_CS) ) || (IN_CHAIN(Y)  && !PIN_EXISTS(Y_CS) ) \
+    || (IN_CHAIN(Z)  && !PIN_EXISTS(Z_CS) ) || (IN_CHAIN(X2) && !PIN_EXISTS(X2_CS)) \
+    || (IN_CHAIN(Y2) && !PIN_EXISTS(Y2_CS)) || (IN_CHAIN(Z2) && !PIN_EXISTS(Z2_CS)) \
+    || (IN_CHAIN(Z3) && !PIN_EXISTS(Z3_CS)) || (IN_CHAIN(E0) && !PIN_EXISTS(E0_CS)) \
+    || (IN_CHAIN(E1) && !PIN_EXISTS(E1_CS)) || (IN_CHAIN(E2) && !PIN_EXISTS(E2_CS)) \
+    || (IN_CHAIN(E3) && !PIN_EXISTS(E3_CS)) || (IN_CHAIN(E4) && !PIN_EXISTS(E4_CS)) \
+    || (IN_CHAIN(E5) && !PIN_EXISTS(E5_CS))
+    #error "All chained TMC drivers need a CS pin."
   #else
-    #if X_CHAIN_POS
+    #if IN_CHAIN(X)
       #define CS_COMPARE X_CS_PIN
-    #elif Y_CHAIN_POS
+    #elif IN_CHAIN(Y)
       #define CS_COMPARE Y_CS_PIN
-    #elif Z_CHAIN_POS
+    #elif IN_CHAIN(Z)
       #define CS_COMPARE Z_CS_PIN
-    #elif X2_CHAIN_POS
+    #elif IN_CHAIN(X2)
       #define CS_COMPARE X2_CS_PIN
-    #elif Y2_CHAIN_POS
+    #elif IN_CHAIN(Y2)
       #define CS_COMPARE Y2_CS_PIN
-    #elif Z2_CHAIN_POS
+    #elif IN_CHAIN(Z2)
       #define CS_COMPARE Z2_CS_PIN
-    #elif Z3_CHAIN_POS
+    #elif IN_CHAIN(Z3)
       #define CS_COMPARE Z3_CS_PIN
-    #elif E0_CHAIN_POS
+    #elif IN_CHAIN(E0)
       #define CS_COMPARE E0_CS_PIN
-    #elif E1_CHAIN_POS
+    #elif IN_CHAIN(E1)
       #define CS_COMPARE E1_CS_PIN
-    #elif E2_CHAIN_POS
+    #elif IN_CHAIN(E2)
       #define CS_COMPARE E2_CS_PIN
-    #elif E3_CHAIN_POS
+    #elif IN_CHAIN(E3)
       #define CS_COMPARE E3_CS_PIN
-    #elif E4_CHAIN_POS
+    #elif IN_CHAIN(E4)
       #define CS_COMPARE E4_CS_PIN
-    #elif E5_CHAIN_POS
+    #elif IN_CHAIN(E5)
       #define CS_COMPARE E5_CS_PIN
-    #else
-      #error "With TMC_USE_CHAIN some TMC drivers should be chained."
     #endif
-    #if  (X_CHAIN_POS  && X_CS_PIN  != CS_COMPARE) \
-      || (Y_CHAIN_POS  && Y_CS_PIN  != CS_COMPARE) \
-      || (Z_CHAIN_POS  && Z_CS_PIN  != CS_COMPARE) \
-      || (X2_CHAIN_POS && X2_CS_PIN != CS_COMPARE) \
-      || (Y2_CHAIN_POS && Y2_CS_PIN != CS_COMPARE) \
-      || (Z2_CHAIN_POS && Z2_CS_PIN != CS_COMPARE) \
-      || (Z3_CHAIN_POS && Z3_CS_PIN != CS_COMPARE) \
-      || (E0_CHAIN_POS && E0_CS_PIN != CS_COMPARE) \
-      || (E1_CHAIN_POS && E1_CS_PIN != CS_COMPARE) \
-      || (E2_CHAIN_POS && E2_CS_PIN != CS_COMPARE) \
-      || (E3_CHAIN_POS && E3_CS_PIN != CS_COMPARE) \
-      || (E4_CHAIN_POS && E4_CS_PIN != CS_COMPARE) \
-      || (E5_CHAIN_POS && E5_CS_PIN != CS_COMPARE)
-      #error "With TMC_USE_CHAIN all TMC drivers must use the same CS pin."
+    #if  (IN_CHAIN(X)  && X_CS_PIN  != CS_COMPARE) || (IN_CHAIN(Y)  && Y_CS_PIN  != CS_COMPARE) \
+      || (IN_CHAIN(Z)  && Z_CS_PIN  != CS_COMPARE) || (IN_CHAIN(X2) && X2_CS_PIN != CS_COMPARE) \
+      || (IN_CHAIN(Y2) && Y2_CS_PIN != CS_COMPARE) || (IN_CHAIN(Z2) && Z2_CS_PIN != CS_COMPARE) \
+      || (IN_CHAIN(Z3) && Z3_CS_PIN != CS_COMPARE) || (IN_CHAIN(E0) && E0_CS_PIN != CS_COMPARE) \
+      || (IN_CHAIN(E1) && E1_CS_PIN != CS_COMPARE) || (IN_CHAIN(E2) && E2_CS_PIN != CS_COMPARE) \
+      || (IN_CHAIN(E3) && E3_CS_PIN != CS_COMPARE) || (IN_CHAIN(E4) && E4_CS_PIN != CS_COMPARE) \
+      || (IN_CHAIN(E5) && E5_CS_PIN != CS_COMPARE)
+      #error "All chained TMC drivers must use the same CS pin."
     #endif
   #endif
   #undef CS_COMPARE
-#endif // TMC_USE_CHAIN
+#endif
+#undef IN_CHAIN
 
 #if ENABLED(DELTA) && (ENABLED(STEALTHCHOP_XY) != ENABLED(STEALTHCHOP_Z))
   #error "STEALTHCHOP_XY and STEALTHCHOP_Z must be the same on DELTA."

Marlin/src/module/stepper/trinamic.cpp

 //   AI = Axis Enum Index
 // SWHW = SW/SH UART selection
 #if ENABLED(TMC_USE_SW_SPI)
-  #define __TMC_SPI_DEFINE(IC, ST, L, AI) TMCMarlin<IC##Stepper, L, AI> stepper##ST(ST##_CS_PIN, ST##_RSENSE, TMC_SW_MOSI, TMC_SW_MISO, TMC_SW_SCK)
+  #define __TMC_SPI_DEFINE(IC, ST, L, AI) TMCMarlin<IC##Stepper, L, AI> stepper##ST(ST##_CS_PIN, ST##_RSENSE, TMC_SW_MOSI, TMC_SW_MISO, TMC_SW_SCK, ST##_CHAIN_POS)
 #else
-  #define __TMC_SPI_DEFINE(IC, ST, L, AI) TMCMarlin<IC##Stepper, L, AI> stepper##ST(ST##_CS_PIN, ST##_RSENSE)
+  #define __TMC_SPI_DEFINE(IC, ST, L, AI) TMCMarlin<IC##Stepper, L, AI> stepper##ST(ST##_CS_PIN, ST##_RSENSE, ST##_CHAIN_POS)
 #endif
 
 #define TMC_UART_HW_DEFINE(IC, ST, L, AI) TMCMarlin<IC##Stepper, L, AI> stepper##ST(&ST##_HARDWARE_SERIAL, ST##_RSENSE, ST##_SLAVE_ADDRESS)
     #endif
   };
 
-  #if TMC_USE_CHAIN
-
-    enum TMC_axis_enum : unsigned char { _, X, Y, Z, X2, Y2, Z2, Z3, E0, E1, E2, E3, E4, E5 };
-    #define __TMC_CHAIN(Q,V) do{ stepper##Q.set_chain_info(Q,V); }while(0)
-    #define _TMC_CHAIN(Q) __TMC_CHAIN(Q, Q##_CHAIN_POS)
-
-    #if AXIS_HAS_SPI(X)                  // First set chain array to uninitialized
-      __TMC_CHAIN(X, 0);
-    #endif
-    #if AXIS_HAS_SPI(X2)
-      __TMC_CHAIN(X2, 0);
-    #endif
-    #if AXIS_HAS_SPI(Y)
-      __TMC_CHAIN(Y, 0);
-    #endif
-    #if AXIS_HAS_SPI(Y2)
-      __TMC_CHAIN(Y2, 0);
-    #endif
-    #if AXIS_HAS_SPI(Z)
-      __TMC_CHAIN(Z, 0);
-    #endif
-    #if AXIS_HAS_SPI(Z2)
-      __TMC_CHAIN(Z2, 0);
-    #endif
-    #if AXIS_HAS_SPI(Z3)
-      __TMC_CHAIN(Z3, 0);
-    #endif
-    #if AXIS_HAS_SPI(E0)
-      __TMC_CHAIN(E0, 0);
-    #endif
-    #if AXIS_HAS_SPI(E1)
-      __TMC_CHAIN(E1, 0);
-    #endif
-    #if AXIS_HAS_SPI(E2)
-      __TMC_CHAIN(E2, 0);
-    #endif
-    #if AXIS_HAS_SPI(E3)
-      __TMC_CHAIN(E3, 0);
-    #endif
-    #if AXIS_HAS_SPI(E4)
-      __TMC_CHAIN(E4, 0);
-    #endif
-    #if AXIS_HAS_SPI(E5)
-      __TMC_CHAIN(E5, 0);
-    #endif
-
-    #if AXIS_HAS_SPI(X) && X_CHAIN_POS             // Now set up the SPI chain
-      _TMC_CHAIN(X);
-    #endif
-    #if AXIS_HAS_SPI(X2) && X2_CHAIN_POS
-      _TMC_CHAIN(X2);
-    #endif
-    #if AXIS_HAS_SPI(Y) && Y_CHAIN_POS
-      _TMC_CHAIN(Y);
-    #endif
-    #if AXIS_HAS_SPI(Y2) && Y2_CHAIN_POS
-      _TMC_CHAIN(Y2);
-    #endif
-    #if AXIS_HAS_SPI(Z) && Z_CHAIN_POS
-      _TMC_CHAIN(Z);
-    #endif
-    #if AXIS_HAS_SPI(Z2) && Z2_CHAIN_POS
-      _TMC_CHAIN(Z2);
-    #endif
-    #if AXIS_HAS_SPI(Z3) && Z3_CHAIN_POS
-      _TMC_CHAIN(Z3);
-    #endif
-    #if AXIS_HAS_SPI(E0) && E0_CHAIN_POS
-      _TMC_CHAIN(E0);
-    #endif
-    #if AXIS_HAS_SPI(E1) && E1_CHAIN_POS
-      _TMC_CHAIN(E1);
-    #endif
-    #if AXIS_HAS_SPI(E2) && E2_CHAIN_POS
-      _TMC_CHAIN(E2);
-    #endif
-    #if AXIS_HAS_SPI(E3) && E3_CHAIN_POS
-      _TMC_CHAIN(E3);
-    #endif
-    #if AXIS_HAS_SPI(E4) && E4_CHAIN_POS
-      _TMC_CHAIN(E4);
-    #endif
-    #if AXIS_HAS_SPI(E5) && E5_CHAIN_POS
-      _TMC_CHAIN(E5);
-    #endif
-  #endif // TMC_USE_CHAIN
-
   #if AXIS_IS_TMC(X)
     _TMC_INIT(X, STEALTH_AXIS_XY);
   #endif

config/default/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/3DFabXYZ/Migbot/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/ADIMLab/Gantry v1/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/ADIMLab/Gantry v2/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/AlephObjects/TAZ4/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Alfawise/U20-bltouch/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Alfawise/U20/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/AliExpress/UM2pExt/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Anet/A2/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Anet/A2plus/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Anet/A6/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Anet/A8/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Anet/A8plus/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Anet/E16/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/AnyCubic/i3/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/ArmEd/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/BIBO/TouchX/cyclops/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/BIBO/TouchX/default/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/BQ/Hephestos/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/BQ/Hephestos_2/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/BQ/WITBOX/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Cartesio/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Creality/CR-10/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Creality/CR-10S/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Creality/CR-10_5S/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Creality/CR-10mini/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Creality/CR-20 Pro/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Creality/CR-20/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Creality/CR-8/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Creality/Ender-2/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Creality/Ender-3/Configuration_adv.h

     #define X_CURRENT     580  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     580
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     580
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    650
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Creality/Ender-4/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Creality/Ender-5/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Dagoma/Disco Ultimate/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/EVNOVO (Artillery)/Sidewinder X1/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Einstart-S/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/FYSETC/AIO_II/Configuration_adv.h

     #define X_CURRENT     700  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     650
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    650
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/FYSETC/Cheetah 1.2/BLTouch/Configuration_adv.h

     #define X_CURRENT     700  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     500
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    650
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/FYSETC/Cheetah 1.2/base/Configuration_adv.h

     #define X_CURRENT     700  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     500
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    650
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/FYSETC/Cheetah/BLTouch/Configuration_adv.h

     #define X_CURRENT     700  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     500
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    650
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/FYSETC/Cheetah/base/Configuration_adv.h

     #define X_CURRENT     700  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     500
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    650
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/FYSETC/F6_13/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Felix/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/FlashForge/CreatorPro/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/FolgerTech/i3-2020/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Formbot/Raptor/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Formbot/T_Rex_2+/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Formbot/T_Rex_3/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Geeetech/A10/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Geeetech/A10M/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Geeetech/A20M/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Geeetech/MeCreator2/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Geeetech/Prusa i3 Pro C/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Geeetech/Prusa i3 Pro W/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/HMS434/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Infitary/i3-M508/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/JGAurora/A1/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/JGAurora/A5/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/JGAurora/A5S/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/MakerParts/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Malyan/M150/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Malyan/M200/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Micromake/C1/enhanced/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Mks/Robin/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Mks/Sbase/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/RapideLite/RL200/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/RigidBot/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/SCARA/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/STM32/Black_STM32F407VET6/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Sanguinololu/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Tevo/Michelangelo/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Tevo/Tarantula Pro/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Tevo/Tornado/V1 (MKS Base)/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Tevo/Tornado/V2 (MKS GEN-L)/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/TheBorg/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/TinyBoy2/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Tronxy/X3A/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Tronxy/X5S-2E/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/UltiMachine/Archim1/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/UltiMachine/Archim2/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/VORONDesign/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Velleman/K8200/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Velleman/K8400/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/WASP/PowerWASP/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Wanhao/Duplicator 6/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/Wanhao/Duplicator i3 Mini/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/delta/Anycubic/Kossel/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/delta/Dreammaker/Overlord/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/delta/Dreammaker/Overlord_Pro/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/delta/FLSUN/auto_calibrate/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/delta/FLSUN/kossel/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/delta/FLSUN/kossel_mini/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/delta/Geeetech/Rostock 301/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**

config/examples/delta/MKS/SBASE/Configuration_adv.h

     #define X_CURRENT     800  // (mA) RMS current. Multiply by 1.414 for peak current.
     #define X_MICROSTEPS   16  // 0..256
     #define X_RSENSE     0.11
-    #define X_CHAIN_POS     0  // 0 - Not chained, 1 - MCU MOSI connected, 2 - next in chain, ...
+    #define X_CHAIN_POS    -1  // <=0 : Not chained. 1 : MCU MOSI connected. 2 : Next in chain, ...
   #endif
 
   #if AXIS_IS_TMC(X2)
     #define X2_CURRENT    800
     #define X2_MICROSTEPS  16
     #define X2_RSENSE    0.11
-    #define X2_CHAIN_POS    0
+    #define X2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Y)
     #define Y_CURRENT     800
     #define Y_MICROSTEPS   16
     #define Y_RSENSE     0.11
-    #define Y_CHAIN_POS     0
+    #define Y_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Y2)
     #define Y2_CURRENT    800
     #define Y2_MICROSTEPS  16
     #define Y2_RSENSE    0.11
-    #define Y2_CHAIN_POS    0
+    #define Y2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z)
     #define Z_CURRENT     800
     #define Z_MICROSTEPS   16
     #define Z_RSENSE     0.11
-    #define Z_CHAIN_POS     0
+    #define Z_CHAIN_POS    -1
   #endif
 
   #if AXIS_IS_TMC(Z2)
     #define Z2_CURRENT    800
     #define Z2_MICROSTEPS  16
     #define Z2_RSENSE    0.11
-    #define Z2_CHAIN_POS    0
+    #define Z2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(Z3)
     #define Z3_CURRENT    800
     #define Z3_MICROSTEPS  16
     #define Z3_RSENSE    0.11
-    #define Z3_CHAIN_POS    0
+    #define Z3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E0)
     #define E0_CURRENT    800
     #define E0_MICROSTEPS  16
     #define E0_RSENSE    0.11
-    #define E0_CHAIN_POS    0
+    #define E0_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E1)
     #define E1_CURRENT    800
     #define E1_MICROSTEPS  16
     #define E1_RSENSE    0.11
-    #define E1_CHAIN_POS    0
+    #define E1_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E2)
     #define E2_CURRENT    800
     #define E2_MICROSTEPS  16
     #define E2_RSENSE    0.11
-    #define E2_CHAIN_POS    0
+    #define E2_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E3)
     #define E3_CURRENT    800
     #define E3_MICROSTEPS  16
     #define E3_RSENSE    0.11
-    #define E3_CHAIN_POS    0
+    #define E3_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E4)
     #define E4_CURRENT    800
     #define E4_MICROSTEPS  16
     #define E4_RSENSE    0.11
-    #define E4_CHAIN_POS    0
+    #define E4_CHAIN_POS   -1
   #endif
 
   #if AXIS_IS_TMC(E5)
     #define E5_CURRENT    800
     #define E5_MICROSTEPS  16
     #define E5_RSENSE    0.11
-    #define E5_CHAIN_POS    0
+    #define E5_CHAIN_POS   -1
   #endif
 
   /**
     #define X_OVERCURRENT   2000  // (mA) Current where the driver detects an over current (VALID: 375 x (1 - 16) - 6A max - rounds down)
     #define X_STALLCURRENT  1500  // (mA) Current where the driver detects a stall (VALID: 31.25 * (1-128) -  4A max - rounds down)
     #define X_MAX_VOLTAGE    127  // 0-255, Maximum effective voltage seen by stepper
-    #define X_CHAIN_POS        0  // Position in SPI chain, 0=Not in chain, 1=Nearest MOSI
+    #define X_CHAIN_POS       -1  // Position in SPI chain. (<=0 : Not in chain. 1 : Nearest MOSI)
   #endif
 
   #if AXIS_DRIVER_TYPE_X2(L6470)
     #define X2_OVERCURRENT    2000
     #define X2_STALLCURRENT   1500
     #define X2_MAX_VOLTAGE     127
-    #define X2_CHAIN_POS         0
+    #define X2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y(L6470)
     #define Y_OVERCURRENT     2000
     #define Y_STALLCURRENT    1500
     #define Y_MAX_VOLTAGE      127
-    #define Y_CHAIN_POS          0
+    #define Y_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Y2(L6470)
     #define Y2_OVERCURRENT    2000
     #define Y2_STALLCURRENT   1500
     #define Y2_MAX_VOLTAGE     127
-    #define Y2_CHAIN_POS         0
+    #define Y2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z(L6470)
     #define Z_OVERCURRENT     2000
     #define Z_STALLCURRENT    1500
     #define Z_MAX_VOLTAGE      127
-    #define Z_CHAIN_POS          0
+    #define Z_CHAIN_POS         -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z2(L6470)
     #define Z2_OVERCURRENT    2000
     #define Z2_STALLCURRENT   1500
     #define Z2_MAX_VOLTAGE     127
-    #define Z2_CHAIN_POS         0
+    #define Z2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_Z3(L6470)
     #define Z3_OVERCURRENT    2000
     #define Z3_STALLCURRENT   1500
     #define Z3_MAX_VOLTAGE     127
-    #define Z3_CHAIN_POS         0
+    #define Z3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E0(L6470)
     #define E0_OVERCURRENT    2000
     #define E0_STALLCURRENT   1500
     #define E0_MAX_VOLTAGE     127
-    #define E0_CHAIN_POS         0
+    #define E0_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E1(L6470)
     #define E1_OVERCURRENT    2000
     #define E1_STALLCURRENT   1500
     #define E1_MAX_VOLTAGE     127
-    #define E1_CHAIN_POS         0
+    #define E1_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E2(L6470)
     #define E2_OVERCURRENT    2000
     #define E2_STALLCURRENT   1500
     #define E2_MAX_VOLTAGE     127
-    #define E2_CHAIN_POS         0
+    #define E2_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E3(L6470)
     #define E3_OVERCURRENT    2000
     #define E3_STALLCURRENT   1500
     #define E3_MAX_VOLTAGE     127
-    #define E3_CHAIN_POS         0
+    #define E3_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E4(L6470)
     #define E4_OVERCURRENT    2000
     #define E4_STALLCURRENT   1500
     #define E4_MAX_VOLTAGE     127
-    #define E4_CHAIN_POS         0
+    #define E4_CHAIN_POS        -1
   #endif
 
   #if AXIS_DRIVER_TYPE_E5(L6470)
     #define E5_OVERCURRENT    2000
     #define E5_STALLCURRENT   1500
     #define E5_MAX_VOLTAGE     127
-    #define E5_CHAIN_POS         0
+    #define E5_CHAIN_POS        -1
   #endif
 
   /**