HAL and serial cleanup

Co-Authored-By: Jason Smith <20053467+sjasonsmith@users.noreply.github.com>

Marlin/src/HAL/AVR/HAL.h

@@ -81,12 +81,7 @@ typedef int8_t pin_t;
 
 // Serial ports
 #ifdef USBCON
-  #if ENABLED(BLUETOOTH)
-    #define MYSERIAL0 bluetoothSerial
-  #else
-    #define MYSERIAL0 Serial
-  #endif
-  #define NUM_SERIAL 1
+  #define MYSERIAL0 TERN(BLUETOOTH, bluetoothSerial, Serial)
 #else
   #if !WITHIN(SERIAL_PORT, -1, 3)
     #error "SERIAL_PORT must be from -1 to 3. Please update your configuration."
@@ -97,36 +92,22 @@ typedef int8_t pin_t;
   #ifdef SERIAL_PORT_2
     #if !WITHIN(SERIAL_PORT_2, -1, 3)
       #error "SERIAL_PORT_2 must be from -1 to 3. Please update your configuration."
-    #elif SERIAL_PORT_2 == SERIAL_PORT
-      #error "SERIAL_PORT_2 must be different than SERIAL_PORT. Please update your configuration."
     #endif
     #define MYSERIAL1 customizedSerial2
-    #define NUM_SERIAL 2
-  #else
-    #define NUM_SERIAL 1
   #endif
 #endif
 
 #ifdef DGUS_SERIAL_PORT
   #if !WITHIN(DGUS_SERIAL_PORT, -1, 3)
     #error "DGUS_SERIAL_PORT must be from -1 to 3. Please update your configuration."
-  #elif DGUS_SERIAL_PORT == SERIAL_PORT
-    #error "DGUS_SERIAL_PORT must be different than SERIAL_PORT. Please update your configuration."
-  #elif defined(SERIAL_PORT_2) && DGUS_SERIAL_PORT == SERIAL_PORT_2
-    #error "DGUS_SERIAL_PORT must be different than SERIAL_PORT_2. Please update your configuration."
   #endif
   #define DGUS_SERIAL internalDgusSerial
-
   #define DGUS_SERIAL_GET_TX_BUFFER_FREE DGUS_SERIAL.get_tx_buffer_free
 #endif
 
 #ifdef ANYCUBIC_LCD_SERIAL_PORT
   #if !WITHIN(ANYCUBIC_LCD_SERIAL_PORT, -1, 3)
     #error "ANYCUBIC_LCD_SERIAL_PORT must be from -1 to 3. Please update your configuration."
-  #elif ANYCUBIC_LCD_SERIAL_PORT == SERIAL_PORT
-    #error "ANYCUBIC_LCD_SERIAL_PORT must be different than SERIAL_PORT. Please update your configuration."
-  #elif defined(SERIAL_PORT_2) && ANYCUBIC_LCD_SERIAL_PORT == SERIAL_PORT_2
-    #error "ANYCUBIC_LCD_SERIAL_PORT must be different than SERIAL_PORT_2. Please update your configuration."
   #endif
   #define ANYCUBIC_LCD_SERIAL anycubicLcdSerial
 #endif

Marlin/src/HAL/AVR/MarlinSerial.cpp

@@ -712,11 +712,11 @@
   }
 
   // Hookup ISR handlers
-  ISR(SERIAL_REGNAME(USART,SERIAL_PORT,_RX_vect)) {
+  ISR(SERIAL_REGNAME(USART, SERIAL_PORT, _RX_vect)) {
     MarlinSerial<MarlinSerialCfg<SERIAL_PORT>>::store_rxd_char();
   }
 
-  ISR(SERIAL_REGNAME(USART,SERIAL_PORT,_UDRE_vect)) {
+  ISR(SERIAL_REGNAME(USART, SERIAL_PORT, _UDRE_vect)) {
     MarlinSerial<MarlinSerialCfg<SERIAL_PORT>>::_tx_udr_empty_irq();
   }
 
@@ -729,11 +729,11 @@
   #ifdef SERIAL_PORT_2
 
     // Hookup ISR handlers
-    ISR(SERIAL_REGNAME(USART,SERIAL_PORT_2,_RX_vect)) {
+    ISR(SERIAL_REGNAME(USART, SERIAL_PORT_2, _RX_vect)) {
       MarlinSerial<MarlinSerialCfg<SERIAL_PORT_2>>::store_rxd_char();
     }
 
-    ISR(SERIAL_REGNAME(USART,SERIAL_PORT_2,_UDRE_vect)) {
+    ISR(SERIAL_REGNAME(USART, SERIAL_PORT_2, _UDRE_vect)) {
       MarlinSerial<MarlinSerialCfg<SERIAL_PORT_2>>::_tx_udr_empty_irq();
     }
 
@@ -749,11 +749,11 @@
 
 #ifdef INTERNAL_SERIAL_PORT
 
-  ISR(SERIAL_REGNAME(USART,INTERNAL_SERIAL_PORT,_RX_vect)) {
+  ISR(SERIAL_REGNAME(USART, INTERNAL_SERIAL_PORT, _RX_vect)) {
     MarlinSerial<MarlinInternalSerialCfg<INTERNAL_SERIAL_PORT>>::store_rxd_char();
   }
 
-  ISR(SERIAL_REGNAME(USART,INTERNAL_SERIAL_PORT,_UDRE_vect)) {
+  ISR(SERIAL_REGNAME(USART, INTERNAL_SERIAL_PORT, _UDRE_vect)) {
     MarlinSerial<MarlinInternalSerialCfg<INTERNAL_SERIAL_PORT>>::_tx_udr_empty_irq();
   }
 
@@ -776,11 +776,11 @@
     return ret;
   }
 
-  ISR(SERIAL_REGNAME(USART,DGUS_SERIAL_PORT,_RX_vect)) {
+  ISR(SERIAL_REGNAME(USART, DGUS_SERIAL_PORT, _RX_vect)) {
     MarlinSerial<MarlinInternalSerialCfg<DGUS_SERIAL_PORT>>::store_rxd_char();
   }
 
-  ISR(SERIAL_REGNAME(USART,DGUS_SERIAL_PORT,_UDRE_vect)) {
+  ISR(SERIAL_REGNAME(USART, DGUS_SERIAL_PORT, _UDRE_vect)) {
     MarlinSerial<MarlinInternalSerialCfg<DGUS_SERIAL_PORT>>::_tx_udr_empty_irq();
   }
 
@@ -794,11 +794,11 @@
 
 #ifdef ANYCUBIC_LCD_SERIAL_PORT
 
-  ISR(SERIAL_REGNAME(USART,ANYCUBIC_LCD_SERIAL_PORT,_RX_vect)) {
+  ISR(SERIAL_REGNAME(USART, ANYCUBIC_LCD_SERIAL_PORT, _RX_vect)) {
     MarlinSerial<AnycubicLcdSerialCfg<ANYCUBIC_LCD_SERIAL_PORT>>::store_rxd_char();
   }
 
-  ISR(SERIAL_REGNAME(USART,ANYCUBIC_LCD_SERIAL_PORT,_UDRE_vect)) {
+  ISR(SERIAL_REGNAME(USART, ANYCUBIC_LCD_SERIAL_PORT, _UDRE_vect)) {
     MarlinSerial<AnycubicLcdSerialCfg<ANYCUBIC_LCD_SERIAL_PORT>>::_tx_udr_empty_irq();
   }
 

Marlin/src/HAL/AVR/MarlinSerial.h

@@ -48,11 +48,11 @@
 
   // These are macros to build serial port register names for the selected SERIAL_PORT (C preprocessor
   // requires two levels of indirection to expand macro values properly)
-  #define SERIAL_REGNAME(registerbase,number,suffix) SERIAL_REGNAME_INTERNAL(registerbase,number,suffix)
+  #define SERIAL_REGNAME(registerbase,number,suffix) _SERIAL_REGNAME(registerbase,number,suffix)
   #if SERIAL_PORT == 0 && (!defined(UBRR0H) || !defined(UDR0)) // use un-numbered registers if necessary
-    #define SERIAL_REGNAME_INTERNAL(registerbase,number,suffix) registerbase##suffix
+    #define _SERIAL_REGNAME(registerbase,number,suffix) registerbase##suffix
   #else
-    #define SERIAL_REGNAME_INTERNAL(registerbase,number,suffix) registerbase##number##suffix
+    #define _SERIAL_REGNAME(registerbase,number,suffix) registerbase##number##suffix
   #endif
 
   // Registers used by MarlinSerial class (expanded depending on selected serial port)

Marlin/src/HAL/DUE/HAL.h

@@ -38,57 +38,34 @@
 
 #include <stdint.h>
 
+#define _MSERIAL(X) Serial##X
+#define MSERIAL(X) _MSERIAL(X)
+#define Serial0 Serial
+
 // Define MYSERIAL0/1 before MarlinSerial includes!
 #if SERIAL_PORT == -1 || ENABLED(EMERGENCY_PARSER)
   #define MYSERIAL0 customizedSerial1
-#elif SERIAL_PORT == 0
-  #define MYSERIAL0 Serial
-#elif SERIAL_PORT == 1
-  #define MYSERIAL0 Serial1
-#elif SERIAL_PORT == 2
-  #define MYSERIAL0 Serial2
-#elif SERIAL_PORT == 3
-  #define MYSERIAL0 Serial3
+#elif WITHIN(SERIAL_PORT, 0, 3)
+  #define MYSERIAL0 MSERIAL(SERIAL_PORT)
 #else
   #error "The required SERIAL_PORT must be from -1 to 3. Please update your configuration."
 #endif
 
 #ifdef SERIAL_PORT_2
-  #if SERIAL_PORT_2 == SERIAL_PORT
-    #error "SERIAL_PORT_2 must be different from SERIAL_PORT. Please update your configuration."
-  #elif SERIAL_PORT_2 == -1 || ENABLED(EMERGENCY_PARSER)
+  #if SERIAL_PORT_2 == -1 || ENABLED(EMERGENCY_PARSER)
     #define MYSERIAL1 customizedSerial2
-  #elif SERIAL_PORT_2 == 0
-    #define MYSERIAL1 Serial
-  #elif SERIAL_PORT_2 == 1
-    #define MYSERIAL1 Serial1
-  #elif SERIAL_PORT_2 == 2
-    #define MYSERIAL1 Serial2
-  #elif SERIAL_PORT_2 == 3
-    #define MYSERIAL1 Serial3
+  #elif WITHIN(SERIAL_PORT_2, 0, 3)
+    #define MYSERIAL1 MSERIAL(SERIAL_PORT_2)
   #else
     #error "SERIAL_PORT_2 must be from -1 to 3. Please update your configuration."
   #endif
-  #define NUM_SERIAL 2
-#else
-  #define NUM_SERIAL 1
 #endif
 
 #ifdef DGUS_SERIAL_PORT
-  #if DGUS_SERIAL_PORT == SERIAL_PORT
-    #error "DGUS_SERIAL_PORT must be different from SERIAL_PORT. Please update your configuration."
-  #elif defined(SERIAL_PORT_2) && DGUS_SERIAL_PORT == SERIAL_PORT_2
-    #error "DGUS_SERIAL_PORT must be different than SERIAL_PORT_2. Please update your configuration."
-  #elif DGUS_SERIAL_PORT == -1
+  #if DGUS_SERIAL_PORT == -1
     #define DGUS_SERIAL internalDgusSerial
-  #elif DGUS_SERIAL_PORT == 0
-    #define DGUS_SERIAL Serial
-  #elif DGUS_SERIAL_PORT == 1
-    #define DGUS_SERIAL Serial1
-  #elif DGUS_SERIAL_PORT == 2
-    #define DGUS_SERIAL Serial2
-  #elif DGUS_SERIAL_PORT == 3
-    #define DGUS_SERIAL Serial3
+  #elif WITHIN(DGUS_SERIAL_PORT, 0, 3)
+    #define DGUS_SERIAL MSERIAL(DGUS_SERIAL_PORT)
   #else
     #error "DGUS_SERIAL_PORT must be from -1 to 3. Please update your configuration."
   #endif

Marlin/src/HAL/ESP32/HAL.h

@@ -58,9 +58,6 @@ extern portMUX_TYPE spinlock;
   #else
     #define MYSERIAL1 webSocketSerial
   #endif
-  #define NUM_SERIAL 2
-#else
-  #define NUM_SERIAL 1
 #endif
 
 #define CRITICAL_SECTION_START() portENTER_CRITICAL(&spinlock)

Marlin/src/HAL/HAL.h

@@ -25,6 +25,12 @@
 
 #include HAL_PATH(.,HAL.h)
 
+#ifdef SERIAL_PORT_2
+  #define NUM_SERIAL 2
+#else
+  #define NUM_SERIAL 1
+#endif
+
 #define HAL_ADC_RANGE _BV(HAL_ADC_RESOLUTION)
 
 #ifndef I2C_ADDRESS

Marlin/src/HAL/LINUX/HAL.h

@@ -62,7 +62,6 @@ uint8_t _getc();
 
 extern HalSerial usb_serial;
 #define MYSERIAL0 usb_serial
-#define NUM_SERIAL 1
 
 #define ST7920_DELAY_1 DELAY_NS(600)
 #define ST7920_DELAY_2 DELAY_NS(750)

Marlin/src/HAL/LINUX/main.cpp

@@ -107,7 +107,7 @@ int main() {
   std::thread write_serial (write_serial_thread);
   std::thread read_serial (read_serial_thread);
 
-  #if NUM_SERIAL > 0
+  #ifdef MYSERIAL0
     MYSERIAL0.begin(BAUDRATE);
     SERIAL_ECHOLNPGM("x86_64 Initialized");
     SERIAL_FLUSHTX();

Marlin/src/HAL/LPC1768/HAL.h

@@ -63,56 +63,33 @@ extern "C" volatile uint32_t _millis;
   #define ST7920_DELAY_3 DELAY_NS(750)
 #endif
 
+#define _MSERIAL(X) MSerial##X
+#define MSERIAL(X) _MSERIAL(X)
+#define MSerial0 MSerial
+
 #if SERIAL_PORT == -1
   #define MYSERIAL0 UsbSerial
-#elif SERIAL_PORT == 0
-  #define MYSERIAL0 MSerial
-#elif SERIAL_PORT == 1
-  #define MYSERIAL0 MSerial1
-#elif SERIAL_PORT == 2
-  #define MYSERIAL0 MSerial2
-#elif SERIAL_PORT == 3
-  #define MYSERIAL0 MSerial3
+#elif WITHIN(SERIAL_PORT, 0, 3)
+  #define MYSERIAL0 MSERIAL(SERIAL_PORT)
 #else
   #error "SERIAL_PORT must be from -1 to 3. Please update your configuration."
 #endif
 
 #ifdef SERIAL_PORT_2
-  #if SERIAL_PORT_2 == SERIAL_PORT
-    #error "SERIAL_PORT_2 must be different than SERIAL_PORT. Please update your configuration."
-  #elif SERIAL_PORT_2 == -1
+  #if SERIAL_PORT_2 == -1
     #define MYSERIAL1 UsbSerial
-  #elif SERIAL_PORT_2 == 0
-    #define MYSERIAL1 MSerial
-  #elif SERIAL_PORT_2 == 1
-    #define MYSERIAL1 MSerial1
-  #elif SERIAL_PORT_2 == 2
-    #define MYSERIAL1 MSerial2
-  #elif SERIAL_PORT_2 == 3
-    #define MYSERIAL1 MSerial3
+  #elif WITHIN(SERIAL_PORT_2, 0, 3)
+    #define MYSERIAL1 MSERIAL(SERIAL_PORT_2)
   #else
     #error "SERIAL_PORT_2 must be from -1 to 3. Please update your configuration."
   #endif
-  #define NUM_SERIAL 2
-#else
-  #define NUM_SERIAL 1
 #endif
 
 #ifdef DGUS_SERIAL_PORT
-  #if DGUS_SERIAL_PORT == SERIAL_PORT
-    #error "DGUS_SERIAL_PORT must be different than SERIAL_PORT. Please update your configuration."
-  #elif defined(SERIAL_PORT_2) && DGUS_SERIAL_PORT == SERIAL_PORT_2
-    #error "DGUS_SERIAL_PORT must be different than SERIAL_PORT_2. Please update your configuration."
-  #elif DGUS_SERIAL_PORT == -1
+  #if DGUS_SERIAL_PORT == -1
     #define DGUS_SERIAL UsbSerial
-  #elif DGUS_SERIAL_PORT == 0
-    #define DGUS_SERIAL MSerial
-  #elif DGUS_SERIAL_PORT == 1
-    #define DGUS_SERIAL MSerial1
-  #elif DGUS_SERIAL_PORT == 2
-    #define DGUS_SERIAL MSerial2
-  #elif DGUS_SERIAL_PORT == 3
-    #define DGUS_SERIAL MSerial3
+  #elif WITHIN(DGUS_SERIAL_PORT, 0, 3)
+    #define DGUS_SERIAL MSERIAL(DGUS_SERIAL_PORT)
   #else
     #error "DGUS_SERIAL_PORT must be from -1 to 3. Please update your configuration."
   #endif

Marlin/src/HAL/LPC1768/inc/SanityCheck.h

@@ -89,6 +89,9 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
  * Serial2 | P0_10 | P0_11 |
  * Serial3 | P0_00 | P0_01 |
  */
+#define ANY_TX(N,V...) DO(IS_TX##N,||,V)
+#define ANY_RX(N,V...) DO(IS_RX##N,||,V)
+
 #if (defined(SERIAL_PORT) && SERIAL_PORT == 0) || (defined(SERIAL_PORT_2) && SERIAL_PORT_2 == 0) || (defined(DGUS_SERIAL_PORT) && DGUS_SERIAL_PORT == 0)
   #define IS_TX0(P) (P == P0_02)
   #define IS_RX0(P) (P == P0_03)
@@ -106,48 +109,56 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
 #if SERIAL_PORT == 1 || SERIAL_PORT_2 == 1 || DGUS_SERIAL_PORT == 1
   #define IS_TX1(P) (P == P0_15)
   #define IS_RX1(P) (P == P0_16)
+  #define _IS_TX1_1 IS_TX1
+  #define _IS_RX1_1 IS_RX1
   #if IS_TX1(TMC_SW_SCK)
     #error "Serial port pins (1) conflict with other pins!"
   #elif HAS_SPI_LCD
     #if IS_TX1(BTN_EN2) || IS_RX1(BTN_EN1)
       #error "Serial port pins (1) conflict with Encoder Buttons!"
-    #elif IS_TX1(SCK_PIN) || IS_TX1(LCD_PINS_D4) || IS_TX1(DOGLCD_SCK) || IS_TX1(LCD_RESET_PIN) || IS_TX1(LCD_PINS_RS) || IS_TX1(SHIFT_CLK) \
-      || IS_RX1(LCD_SDSS) || IS_RX1(LCD_PINS_RS) || IS_RX1(MISO_PIN) || IS_RX1(DOGLCD_A0) || IS_RX1(SS_PIN) || IS_RX1(LCD_SDSS) || IS_RX1(DOGLCD_CS) || IS_RX1(LCD_RESET_PIN) || IS_RX1(LCD_BACKLIGHT_PIN)
+    #elif ANY_TX(1, SCK_PIN, LCD_PINS_D4, DOGLCD_SCK, LCD_RESET_PIN, LCD_PINS_RS, SHIFT_CLK) \
+       || ANY_RX(1, LCD_SDSS, LCD_PINS_RS, MISO_PIN, DOGLCD_A0, SS_PIN, LCD_SDSS, DOGLCD_CS, LCD_RESET_PIN, LCD_BACKLIGHT_PIN)
       #error "Serial port pins (1) conflict with LCD pins!"
     #endif
   #endif
   #undef IS_TX1
   #undef IS_RX1
+  #undef _IS_TX1_1
+  #undef _IS_RX1_1
 #endif
 
 #if SERIAL_PORT == 2 || SERIAL_PORT_2 == 2 || DGUS_SERIAL_PORT == 2
   #define IS_TX2(P) (P == P0_10)
   #define IS_RX2(P) (P == P0_11)
-  #if  IS_TX2(X2_ENABLE_PIN) || IS_RX2(X2_DIR_PIN) || IS_RX2(X2_STEP_PIN) || (AXIS_HAS_SPI(X2) && IS_TX2(X2_CS_PIN))
+  #define _IS_TX2_1 IS_TX2
+  #define _IS_RX2_1 IS_RX2
+  #if IS_TX2(X2_ENABLE_PIN) || ANY_RX(2, X2_DIR_PIN, X2_STEP_PIN) || (AXIS_HAS_SPI(X2) && IS_TX2(X2_CS_PIN))
     #error "Serial port pins (2) conflict with X2 pins!"
-  #elif IS_TX2(Y2_ENABLE_PIN) || IS_RX2(Y2_DIR_PIN) || IS_RX2(Y2_STEP_PIN) || (AXIS_HAS_SPI(Y2) && IS_TX2(Y2_CS_PIN))
+  #elif IS_TX2(Y2_ENABLE_PIN) || ANY_RX(2, Y2_DIR_PIN, Y2_STEP_PIN) || (AXIS_HAS_SPI(Y2) && IS_TX2(Y2_CS_PIN))
     #error "Serial port pins (2) conflict with Y2 pins!"
-  #elif IS_TX2(Z2_ENABLE_PIN) || IS_RX2(Z2_DIR_PIN) || IS_RX2(Z2_STEP_PIN) || (AXIS_HAS_SPI(Z2) && IS_TX2(Z2_CS_PIN))
+  #elif IS_TX2(Z2_ENABLE_PIN) || ANY_RX(2, Z2_DIR_PIN, Z2_STEP_PIN) || (AXIS_HAS_SPI(Z2) && IS_TX2(Z2_CS_PIN))
     #error "Serial port pins (2) conflict with Z2 pins!"
-  #elif IS_TX2(Z3_ENABLE_PIN) || IS_RX2(Z3_DIR_PIN) || IS_RX2(Z3_STEP_PIN) || (AXIS_HAS_SPI(Z3) && IS_TX2(Z3_CS_PIN))
+  #elif IS_TX2(Z3_ENABLE_PIN) || ANY_RX(2, Z3_DIR_PIN, Z3_STEP_PIN) || (AXIS_HAS_SPI(Z3) && IS_TX2(Z3_CS_PIN))
     #error "Serial port pins (2) conflict with Z3 pins!"
-  #elif IS_TX2(Z4_ENABLE_PIN) || IS_RX2(Z4_DIR_PIN) || IS_RX2(Z4_STEP_PIN) || (AXIS_HAS_SPI(Z4) && IS_TX2(Z4_CS_PIN))
+  #elif IS_TX2(Z4_ENABLE_PIN) || ANY_RX(2, Z4_DIR_PIN, Z4_STEP_PIN) || (AXIS_HAS_SPI(Z4) && IS_TX2(Z4_CS_PIN))
     #error "Serial port pins (2) conflict with Z4 pins!"
-  #elif IS_RX2(X_DIR_PIN) || IS_RX2(Y_DIR_PIN)
+  #elif ANY_RX(2, X_DIR_PIN, Y_DIR_PIN)
     #error "Serial port pins (2) conflict with other pins!"
   #elif Y_HOME_DIR < 0 && IS_TX2(Y_STOP_PIN)
     #error "Serial port pins (2) conflict with Y endstop pin!"
   #elif HAS_CUSTOM_PROBE_PIN && IS_TX2(Z_MIN_PROBE_PIN)
     #error "Serial port pins (2) conflict with probe pin!"
-  #elif IS_TX2(X_ENABLE_PIN) || IS_RX2(X_DIR_PIN) || IS_TX2(Y_ENABLE_PIN) || IS_RX2(Y_DIR_PIN)
+  #elif ANY_TX(2, X_ENABLE_PIN, Y_ENABLE_PIN) || ANY_RX(2, X_DIR_PIN, Y_DIR_PIN)
     #error "Serial port pins (2) conflict with X/Y stepper pins!"
   #elif HAS_MULTI_EXTRUDER && (IS_TX2(E1_ENABLE_PIN) || (AXIS_HAS_SPI(E1) && IS_TX2(E1_CS_PIN)))
     #error "Serial port pins (2) conflict with E1 stepper pins!"
-  #elif EXTRUDERS && (IS_RX2(E0_DIR_PIN) || IS_RX2(E0_STEP_PIN))
+  #elif EXTRUDERS && ANY_RX(2, E0_DIR_PIN, E0_STEP_PIN)
     #error "Serial port pins (2) conflict with E stepper pins!"
   #endif
   #undef IS_TX2
   #undef IS_RX2
+  #undef _IS_TX2_1
+  #undef _IS_RX2_1
 #endif
 
 #if SERIAL_PORT == 3 || SERIAL_PORT_2 == 3 || DGUS_SERIAL_PORT == 3
@@ -155,8 +166,7 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
   #define PIN_IS_RX3(P) (P##_PIN == P0_01)
   #if PIN_IS_TX3(X_MIN) || PIN_IS_RX3(X_MAX)
     #error "Serial port pins (3) conflict with X endstop pins!"
-  #elif PIN_IS_TX3(Y_SERIAL_TX) || PIN_IS_TX3(Y_SERIAL_RX) \
-    ||  PIN_IS_RX3(X_SERIAL_TX) || PIN_IS_RX3(X_SERIAL_RX)
+  #elif PIN_IS_TX3(Y_SERIAL_TX) || PIN_IS_TX3(Y_SERIAL_RX) || PIN_IS_RX3(X_SERIAL_TX) || PIN_IS_RX3(X_SERIAL_RX)
     #error "Serial port pins (3) conflict with X/Y axis UART pins!"
   #elif PIN_IS_TX3(X2_DIR) || PIN_IS_RX3(X2_STEP)
     #error "Serial port pins (3) conflict with X2 pins!"
@@ -175,6 +185,9 @@ static_assert(DISABLED(BAUD_RATE_GCODE), "BAUD_RATE_GCODE is not yet supported o
   #undef PIN_IS_RX3
 #endif
 
+#undef ANY_TX
+#undef ANY_RX
+
 //
 // Flag any i2c pin conflicts
 //

Marlin/src/HAL/SAMD51/HAL.h

@@ -35,56 +35,32 @@
 
   // MYSERIAL0 required before MarlinSerial includes!
 
+  #define _MSERIAL(X) Serial##X
+  #define MSERIAL(X) _MSERIAL(INCREMENT(X))
+
   #if SERIAL_PORT == -1
     #define MYSERIAL0 Serial
-  #elif SERIAL_PORT == 0
-    #define MYSERIAL0 Serial1
-  #elif SERIAL_PORT == 1
-    #define MYSERIAL0 Serial2
-  #elif SERIAL_PORT == 2
-    #define MYSERIAL0 Serial3
-  #elif SERIAL_PORT == 3
-    #define MYSERIAL0 Serial4
+  #elif WITHIN(SERIAL_PORT, 0, 3)
+    #define MYSERIAL0 MSERIAL(SERIAL_PORT)
   #else
     #error "SERIAL_PORT must be from -1 to 3. Please update your configuration."
   #endif
 
   #ifdef SERIAL_PORT_2
-    #if SERIAL_PORT_2 == SERIAL_PORT
-      #error "SERIAL_PORT_2 must be different than SERIAL_PORT. Please update your configuration."
-    #elif SERIAL_PORT_2 == -1
+    #if SERIAL_PORT_2 == -1
       #define MYSERIAL1 Serial
-    #elif SERIAL_PORT_2 == 0
-      #define MYSERIAL1 Serial1
-    #elif SERIAL_PORT_2 == 1
-      #define MYSERIAL1 Serial2
-    #elif SERIAL_PORT_2 == 2
-      #define MYSERIAL1 Serial3
-    #elif SERIAL_PORT_2 == 3
-      #define MYSERIAL1 Serial4
+    #elif WITHIN(SERIAL_PORT_2, 0, 3)
+      #define MYSERIAL0 MSERIAL(SERIAL_PORT_2)
     #else
       #error "SERIAL_PORT_2 must be from -1 to 3. Please update your configuration."
     #endif
-    #define NUM_SERIAL 2
-  #else
-    #define NUM_SERIAL 1
   #endif
 
   #ifdef DGUS_SERIAL_PORT
-    #if DGUS_SERIAL_PORT == SERIAL_PORT
-      #error "DGUS_SERIAL_PORT must be different than SERIAL_PORT. Please update your configuration."
-    #elif defined(SERIAL_PORT_2) && DGUS_SERIAL_PORT == SERIAL_PORT_2
-      #error "DGUS_SERIAL_PORT must be different than SERIAL_PORT_2. Please update your configuration."
-    #elif DGUS_SERIAL_PORT == -1
+    #if DGUS_SERIAL_PORT == -1
       #define DGUS_SERIAL Serial
-    #elif DGUS_SERIAL_PORT == 0
-      #define DGUS_SERIAL Serial1
-    #elif DGUS_SERIAL_PORT == 1
-      #define DGUS_SERIAL Serial2
-    #elif DGUS_SERIAL_PORT == 2
-      #define DGUS_SERIAL Serial3
-    #elif DGUS_SERIAL_PORT == 2
-      #define DGUS_SERIAL Serial4
+    #elif WITHIN(DGUS_SERIAL_PORT, 0, 3)
+      #define MYSERIAL0 MSERIAL(DGUS_SERIAL_PORT)
     #else
       #error "DGUS_SERIAL_PORT must be from -1 to 3. Please update your configuration."
     #endif

Marlin/src/HAL/STM32/HAL.h

@@ -43,82 +43,47 @@
 // ------------------------
 // Defines
 // ------------------------
+#define _MSERIAL(X) MSerial##X
+#define MSERIAL(X) _MSERIAL(X)
 
-#if SERIAL_PORT == 0
-  #error "SERIAL_PORT cannot be 0. (Port 0 does not exist.) Please update your configuration."
-#elif SERIAL_PORT == -1
+#if SERIAL_PORT == -1
   #define MYSERIAL0 SerialUSB
-#elif SERIAL_PORT == 1
-  #define MYSERIAL0 MSerial1
-#elif SERIAL_PORT == 2
-  #define MYSERIAL0 MSerial2
-#elif SERIAL_PORT == 3
-  #define MYSERIAL0 MSerial3
-#elif SERIAL_PORT == 4
-  #define MYSERIAL0 MSerial4
-#elif SERIAL_PORT == 5
-  #define MYSERIAL0 MSerial5
-#elif SERIAL_PORT == 6
-  #define MYSERIAL0 MSerial6
+#elif WITHIN(SERIAL_PORT, 1, 6)
+  #define MYSERIAL0 MSERIAL(SERIAL_PORT)
 #else
-  #error "SERIAL_PORT must be from -1 to 6. Please update your configuration."
+  #error "SERIAL_PORT must be -1 or from 1 to 6. Please update your configuration."
 #endif
 
 #ifdef SERIAL_PORT_2
-  #define NUM_SERIAL 2
-  #if SERIAL_PORT_2 == 0
-    #error "SERIAL_PORT_2 cannot be 0. (Port 0 does not exist.) Please update your configuration."
-  #elif SERIAL_PORT_2 == SERIAL_PORT
-    #error "SERIAL_PORT_2 must be different than SERIAL_PORT. Please update your configuration."
-  #elif SERIAL_PORT_2 == -1
+  #if SERIAL_PORT_2 == -1
     #define MYSERIAL1 SerialUSB
-  #elif SERIAL_PORT_2 == 1
-    #define MYSERIAL1 MSerial1
-  #elif SERIAL_PORT_2 == 2
-    #define MYSERIAL1 MSerial2
-  #elif SERIAL_PORT_2 == 3
-    #define MYSERIAL1 MSerial3
-  #elif SERIAL_PORT_2 == 4
-    #define MYSERIAL1 MSerial4
-  #elif SERIAL_PORT_2 == 5
-    #define MYSERIAL1 MSerial5
-  #elif SERIAL_PORT_2 == 6
-    #define MYSERIAL1 MSerial6
+  #elif WITHIN(SERIAL_PORT_2, 1, 6)
+    #define MYSERIAL1 MSERIAL(SERIAL_PORT_2)
   #else
-    #error "SERIAL_PORT_2 must be from -1 to 6. Please update your configuration."
+    #error "SERIAL_PORT_2 must be -1 or from 1 to 6. Please update your configuration."
   #endif
-#else
-  #define NUM_SERIAL 1
 #endif
 
 #if HAS_DGUS_LCD
-  #if DGUS_SERIAL_PORT == 0
-    #error "DGUS_SERIAL_PORT cannot be 0. (Port 0 does not exist.) Please update your configuration."
-  #elif DGUS_SERIAL_PORT == SERIAL_PORT
-    #error "DGUS_SERIAL_PORT must be different than SERIAL_PORT. Please update your configuration."
-  #elif defined(SERIAL_PORT_2) && DGUS_SERIAL_PORT == SERIAL_PORT_2
-    #error "DGUS_SERIAL_PORT must be different than SERIAL_PORT_2. Please update your configuration."
-  #elif DGUS_SERIAL_PORT == -1
+  #if DGUS_SERIAL_PORT == -1
     #define DGUS_SERIAL SerialUSB
-  #elif DGUS_SERIAL_PORT == 1
-    #define DGUS_SERIAL MSerial1
-  #elif DGUS_SERIAL_PORT == 2
-    #define DGUS_SERIAL MSerial2
-  #elif DGUS_SERIAL_PORT == 3
-    #define DGUS_SERIAL MSerial3
-  #elif DGUS_SERIAL_PORT == 4
-    #define DGUS_SERIAL MSerial4
-  #elif DGUS_SERIAL_PORT == 5
-    #define DGUS_SERIAL MSerial5
-  #elif DGUS_SERIAL_PORT == 6
-    #define DGUS_SERIAL MSerial6
+  #elif WITHIN(DGUS_SERIAL_PORT, 1, 6)
+    #define DGUS_SERIAL MSERIAL(DGUS_SERIAL_PORT)
   #else
-    #error "DGUS_SERIAL_PORT must be from -1 to 6. Please update your configuration."
+    #error "DGUS_SERIAL_PORT must be -1 or from 1 to 6. Please update your configuration."
   #endif
-
   #define DGUS_SERIAL_GET_TX_BUFFER_FREE DGUS_SERIAL.availableForWrite
 #endif
 
+#if ENABLED(MALYAN_LCD)
+  #if LCD_SERIAL_PORT == -1
+    #define LCD_SERIAL SerialUSB
+  #elif WITHIN(LCD_SERIAL_PORT, 1, 6)
+    #define LCD_SERIAL MSERIAL(LCD_SERIAL_PORT)
+  #else
+    #error "LCD_SERIAL_PORT must be -1 or from 1 to 6. Please update your configuration."
+  #endif
+#endif
 
 /**
  * TODO: review this to return 1 for pins that are not analog input

Marlin/src/HAL/STM32/pinsDebug_STM32GENERIC.h

@@ -98,7 +98,7 @@ static inline void pwm_details(const pin_t pin) {
     timer_dev * const tdev = PIN_MAP[pin].timer_device;
     const uint8_t channel = PIN_MAP[pin].timer_channel;
     const char num = (
-      #if defined(STM32_HIGH_DENSITY) || defined(STM32_XL_DENSITY)
+      #if EITHER(STM32_HIGH_DENSITY, STM32_XL_DENSITY)
         tdev == &timer8 ? '8' :
         tdev == &timer5 ? '5' :
       #endif

Marlin/src/HAL/STM32F1/HAL.h

@@ -53,7 +53,7 @@
 // ------------------------
 
 #ifndef STM32_FLASH_SIZE
-  #if defined(MCU_STM32F103RE) || defined(MCU_STM32F103VE)
+  #if EITHER(MCU_STM32F103RE, MCU_STM32F103VE)
     #define STM32_FLASH_SIZE 512
   #else
     #define STM32_FLASH_SIZE 256
@@ -106,9 +106,6 @@
   #else
     #error "SERIAL_PORT_2 must be from -1 to 5. Please update your configuration."
   #endif
-  #define NUM_SERIAL 2
-#else
-  #define NUM_SERIAL 1
 #endif
 
 #ifdef DGUS_SERIAL

Marlin/src/HAL/STM32F1/MarlinSerial.h

@@ -30,6 +30,7 @@
   #include "../../feature/e_parser.h"
 #endif
 
+// Increase priority of serial interrupts, to reduce overflow errors
 #define UART_IRQ_PRIO 1
 
 class MarlinSerial : public HardwareSerial {

Marlin/src/HAL/STM32F1/sdio.cpp

@@ -26,7 +26,7 @@
 
 #include "../../inc/MarlinConfig.h" // Allow pins/pins.h to set density
 
-#if defined(STM32_HIGH_DENSITY) || defined(STM32_XL_DENSITY)
+#if EITHER(STM32_HIGH_DENSITY, STM32_XL_DENSITY)
 
 #include "sdio.h"
 

Marlin/src/HAL/STM32_F4_F7/HAL.h

@@ -46,24 +46,16 @@
 // Serial override
 //extern HalSerial usb_serial;
 
+#define _MSERIAL(X) SerialUART##X
+#define MSERIAL(X) _MSERIAL(X)
+#define SerialUART0 Serial1
+
 #if defined(STM32F4) && SERIAL_PORT == 0
   #error "SERIAL_PORT cannot be 0. (Port 0 does not exist.) Please update your configuration."
 #elif SERIAL_PORT == -1
   #define MYSERIAL0 SerialUSB
-#elif SERIAL_PORT == 0
-  #define MYSERIAL0 Serial1
-#elif SERIAL_PORT == 1
-  #define MYSERIAL0 SerialUART1
-#elif SERIAL_PORT == 2
-  #define MYSERIAL0 SerialUART2
-#elif SERIAL_PORT == 3
-  #define MYSERIAL0 SerialUART3
-#elif SERIAL_PORT == 4
-  #define MYSERIAL0 SerialUART4
-#elif SERIAL_PORT == 5
-  #define MYSERIAL0 SerialUART5
-#elif SERIAL_PORT == 6
-  #define MYSERIAL0 SerialUART6
+#elif WITHIN(SERIAL_PORT, 0, 6)
+  #define MYSERIAL0 MSERIAL(SERIAL_PORT)
 #else
   #error "SERIAL_PORT must be from -1 to 6. Please update your configuration."
 #endif
@@ -71,55 +63,22 @@
 #ifdef SERIAL_PORT_2
   #if defined(STM32F4) && SERIAL_PORT_2 == 0
     #error "SERIAL_PORT_2 cannot be 0. (Port 0 does not exist.) Please update your configuration."
-  #elif SERIAL_PORT_2 == SERIAL_PORT
-    #error "SERIAL_PORT_2 must be different than SERIAL_PORT. Please update your configuration."
   #elif SERIAL_PORT_2 == -1
     #define MYSERIAL1 SerialUSB
-  #elif SERIAL_PORT_2 == 0
-    #define MYSERIAL1 Serial1
-  #elif SERIAL_PORT_2 == 1
-    #define MYSERIAL1 SerialUART1
-  #elif SERIAL_PORT_2 == 2
-    #define MYSERIAL1 SerialUART2
-  #elif SERIAL_PORT_2 == 3
-    #define MYSERIAL1 SerialUART3
-  #elif SERIAL_PORT_2 == 4
-    #define MYSERIAL1 SerialUART4
-  #elif SERIAL_PORT_2 == 5
-    #define MYSERIAL1 SerialUART5
-  #elif SERIAL_PORT_2 == 6
-    #define MYSERIAL1 SerialUART6
+  #elif WITHIN(SERIAL_PORT_2, 0, 6)
+    #define MYSERIAL1 MSERIAL(SERIAL_PORT_2)
   #else
     #error "SERIAL_PORT_2 must be from -1 to 6. Please update your configuration."
   #endif
-  #define NUM_SERIAL 2
-#else
-  #define NUM_SERIAL 1
 #endif
 
 #ifdef DGUS_SERIAL_PORT
   #if defined(STM32F4) && DGUS_SERIAL_PORT == 0
     #error "DGUS_SERIAL_PORT cannot be 0. (Port 0 does not exist.) Please update your configuration."
-  #elif DGUS_SERIAL_PORT == SERIAL_PORT
-    #error "DGUS_SERIAL_PORT must be different than SERIAL_PORT. Please update your configuration."
-  #elif defined(SERIAL_PORT_2) && DGUS_SERIAL_PORT == SERIAL_PORT_2
-    #error "DGUS_SERIAL_PORT must be different than SERIAL_PORT_2. Please update your configuration."
   #elif DGUS_SERIAL_PORT == -1
     #define DGUS_SERIAL SerialUSB
-  #elif DGUS_SERIAL_PORT == 0
-    #define DGUS_SERIAL Serial1
-  #elif DGUS_SERIAL_PORT == 1
-    #define DGUS_SERIAL SerialUART1
-  #elif DGUS_SERIAL_PORT == 2
-    #define DGUS_SERIAL SerialUART2
-  #elif DGUS_SERIAL_PORT == 3
-    #define DGUS_SERIAL SerialUART3
-  #elif DGUS_SERIAL_PORT == 4
-    #define DGUS_SERIAL SerialUART4
-  #elif DGUS_SERIAL_PORT == 5
-    #define DGUS_SERIAL SerialUART5
-  #elif DGUS_SERIAL_PORT == 6
-    #define DGUS_SERIAL SerialUART6
+  #elif WITHIN(DGUS_SERIAL_PORT, 0, 6)
+    #define DGUS_SERIAL MSERIAL(DGUS_SERIAL_PORT)
   #else
     #error "DGUS_SERIAL_PORT must be from -1 to 6. Please update your configuration."
   #endif

Marlin/src/HAL/TEENSY31_32/HAL.h

@@ -49,18 +49,14 @@
   #define IS_TEENSY32 1
 #endif
 
-#define NUM_SERIAL 1
+#define _MSERIAL(X) Serial##X
+#define MSERIAL(X) _MSERIAL(X)
+#define Serial0 Serial
 
 #if SERIAL_PORT == -1
   #define MYSERIAL0 SerialUSB
-#elif SERIAL_PORT == 0
-  #define MYSERIAL0 Serial
-#elif SERIAL_PORT == 1
-  #define MYSERIAL0 Serial1
-#elif SERIAL_PORT == 2
-  #define MYSERIAL0 Serial2
-#elif SERIAL_PORT == 3
-  #define MYSERIAL0 Serial3
+#elif WITHIN(SERIAL_PORT, 0, 3)
+  #define MYSERIAL0 MSERIAL(SERIAL_PORT)
 #endif
 
 #define HAL_SERVO_LIB libServo

Marlin/src/HAL/TEENSY35_36/HAL.h

@@ -54,18 +54,14 @@
   #define IS_TEENSY36 1
 #endif
 
-#define NUM_SERIAL 1
+#define _MSERIAL(X) Serial##X
+#define MSERIAL(X) _MSERIAL(X)
+#define Serial0 Serial
 
 #if SERIAL_PORT == -1
   #define MYSERIAL0 SerialUSB
-#elif SERIAL_PORT == 0
-  #define MYSERIAL0 Serial
-#elif SERIAL_PORT == 1
-  #define MYSERIAL0 Serial1
-#elif SERIAL_PORT == 2
-  #define MYSERIAL0 Serial2
-#elif SERIAL_PORT == 3
-  #define MYSERIAL0 Serial3
+#elif WITHIN(SERIAL_PORT, 0, 3)
+  #define MYSERIAL0 MSERIAL(SERIAL_PORT)
 #endif
 
 #define HAL_SERVO_LIB libServo

Marlin/src/HAL/TEENSY40_41/HAL.h

@@ -50,59 +50,26 @@
   #define IS_TEENSY41 1
 #endif
 
+#define _MSERIAL(X) Serial##X
+#define MSERIAL(X) _MSERIAL(X)
+#define Serial0 Serial
+
 #if SERIAL_PORT == -1
   #define MYSERIAL0 SerialUSB
-#elif SERIAL_PORT == 0
-  #define MYSERIAL0 Serial
-#elif SERIAL_PORT == 1
-  #define MYSERIAL0 Serial1
-#elif SERIAL_PORT == 2
-  #define MYSERIAL0 Serial2
-#elif SERIAL_PORT == 3
-  #define MYSERIAL0 Serial3
-#elif SERIAL_PORT == 4
-  #define MYSERIAL0 Serial4
-#elif SERIAL_PORT == 5
-  #define MYSERIAL0 Serial5
-#elif SERIAL_PORT == 6
-  #define MYSERIAL0 Serial6
-#elif SERIAL_PORT == 7
-  #define MYSERIAL0 Serial7
-#elif SERIAL_PORT == 8
-  #define MYSERIAL0 Serial8
+#elif WITHIN(SERIAL_PORT, 0, 8)
+  #define MYSERIAL0 MSERIAL(SERIAL_PORT)
 #else
   #error "The required SERIAL_PORT must be from -1 to 8. Please update your configuration."
 #endif
 
 #ifdef SERIAL_PORT_2
-  #if SERIAL_PORT_2 == SERIAL_PORT
-    #error "SERIAL_PORT_2 must be different from SERIAL_PORT. Please update your configuration."
-  #elif SERIAL_PORT_2 == -1
+  #if SERIAL_PORT_2 == -1
     #define MYSERIAL1 usbSerial
-  #elif SERIAL_PORT_2 == 0
-    #define MYSERIAL1 Serial
-  #elif SERIAL_PORT_2 == 1
-    #define MYSERIAL1 Serial1
-  #elif SERIAL_PORT_2 == 2
-    #define MYSERIAL1 Serial2
-  #elif SERIAL_PORT_2 == 3
-    #define MYSERIAL1 Serial3
-  #elif SERIAL_PORT_2 == 4
-    #define MYSERIAL1 Serial4
-  #elif SERIAL_PORT_2 == 5
-    #define MYSERIAL1 Serial5
-  #elif SERIAL_PORT_2 == 6
-    #define MYSERIAL1 Serial6
-  #elif SERIAL_PORT_2 == 7
-    #define MYSERIAL1 Serial7
-  #elif SERIAL_PORT_2 == 8
-    #define MYSERIAL1 Serial8
+  #elif WITHIN(SERIAL_PORT_2, 0, 8)
+    #define MYSERIAL0 MSERIAL(SERIAL_PORT_2)
   #else
       #error "SERIAL_PORT_2 must be from -1 to 8. Please update your configuration."
   #endif
-  #define NUM_SERIAL 2
-#else
-  #define NUM_SERIAL 1
 #endif
 
 #define HAL_SERVO_LIB libServo

Marlin/src/MarlinCore.cpp

@@ -912,17 +912,15 @@ void setup() {
     #endif
   #endif
 
-  #if NUM_SERIAL > 0
-    MYSERIAL0.begin(BAUDRATE);
-    uint32_t serial_connect_timeout = millis() + 1000UL;
-    while (!MYSERIAL0 && PENDING(millis(), serial_connect_timeout)) { /*nada*/ }
-    #if HAS_MULTI_SERIAL
-      MYSERIAL1.begin(BAUDRATE);
-      serial_connect_timeout = millis() + 1000UL;
-      while (!MYSERIAL1 && PENDING(millis(), serial_connect_timeout)) { /*nada*/ }
-    #endif
-    SERIAL_ECHO_MSG("start");
+  MYSERIAL0.begin(BAUDRATE);
+  uint32_t serial_connect_timeout = millis() + 1000UL;
+  while (!MYSERIAL0 && PENDING(millis(), serial_connect_timeout)) { /*nada*/ }
+  #if HAS_MULTI_SERIAL
+    MYSERIAL1.begin(BAUDRATE);
+    serial_connect_timeout = millis() + 1000UL;
+    while (!MYSERIAL1 && PENDING(millis(), serial_connect_timeout)) { /*nada*/ }
   #endif
+  SERIAL_ECHO_MSG("start");
 
   #if BOTH(HAS_TFT_LVGL_UI, USE_WIFI_FUNCTION)
     mks_esp_wifi_init();

Marlin/src/gcode/config/M575.cpp

@@ -53,23 +53,10 @@ void GcodeSuite::M575() {
     case 115200: case 250000: case 500000: case 1000000: {
       const int8_t port = parser.intval('P', -99);
       const bool set0 = (port == -99 || port == 0);
-      if (set0) {
-        SERIAL_ECHO_START();
-        SERIAL_ECHOLNPAIR(" Serial "
-          #if HAS_MULTI_SERIAL
-            , '0',
-          #else
-            "0"
-          #endif
-          " baud rate set to ", baud
-        );
-      }
+      if (set0) SERIAL_ECHO_MSG(" Serial ", '0', " baud rate set to ", baud);
       #if HAS_MULTI_SERIAL
         const bool set1 = (port == -99 || port == 1);
-        if (set1) {
-          SERIAL_ECHO_START();
-          SERIAL_ECHOLNPAIR(" Serial ", '1', " baud rate set to ", baud);
-        }
+        if (set1) SERIAL_ECHO_MSG(" Serial ", '1', " baud rate set to ", baud);
       #endif
 
       SERIAL_FLUSH();
@@ -85,4 +72,4 @@ void GcodeSuite::M575() {
   }
 }
 
-#endif // NUM_SERIAL > 0 && BAUD_RATE_GCODE
+#endif // BAUD_RATE_GCODE

Marlin/src/inc/SanityCheck.h

@@ -582,12 +582,10 @@
   #error "SERIAL_XON_XOFF and SERIAL_STATS_* features not supported on USB-native AVR devices."
 #endif
 
-#if SERIAL_PORT > 7
-  #error "Set SERIAL_PORT to the port on your board. Usually this is 0."
-#endif
-
-#if defined(SERIAL_PORT_2) && NUM_SERIAL < 2
-  #error "SERIAL_PORT_2 is not supported for your MOTHERBOARD. Disable it to continue."
+#ifndef SERIAL_PORT
+  #error "SERIAL_PORT must be defined in Configuration.h"
+#elif defined(SERIAL_PORT_2) && SERIAL_PORT_2 == SERIAL_PORT
+  #error "SERIAL_PORT_2 cannot be the same as SERIAL_PORT. Please update your configuration."
 #endif
 
 /**
@@ -2281,6 +2279,36 @@ static_assert(hbm[Z_AXIS] >= 0, "HOMING_BUMP_MM.Z must be greater than or equal
 #endif
 
 /**
+ * Serial displays require a dedicated serial port
+ */
+#if HAS_DGUS_LCD
+  #ifndef DGUS_SERIAL_PORT
+    #error "The DGUS LCD requires DGUS_SERIAL_PORT to be defined in Configuration.h"
+  #elif DGUS_SERIAL_PORT == SERIAL_PORT
+    #error "DGUS_SERIAL_PORT cannot be the same as SERIAL_PORT. Please update your configuration."
+  #elif defined(SERIAL_PORT_2) && DGUS_SERIAL_PORT == SERIAL_PORT_2
+    #error "DGUS_SERIAL_PORT cannot be the same as SERIAL_PORT_2. Please update your configuration."
+  #endif
+#elif ENABLED(MALYAN_LCD)
+  #ifndef LCD_SERIAL_PORT
+    #error "MALYAN_LCD requires LCD_SERIAL_PORT to be defined in Configuration.h"
+  #elif LCD_SERIAL_PORT == SERIAL_PORT
+    #error "LCD_SERIAL_PORT cannot be the same as SERIAL_PORT. Please update your configuration."
+  #elif defined(SERIAL_PORT_2) && LCD_SERIAL_PORT == SERIAL_PORT_2
+    #error "LCD_SERIAL_PORT cannot be the same as SERIAL_PORT_2. Please update your configuration."
+  #endif
+#elif EITHER(ANYCUBIC_LCD_I3MEGA, ANYCUBIC_LCD_CHIRON)
+  #ifndef ANYCUBIC_LCD_SERIAL_PORT
+    #error "The ANYCUBIC LCD requires ANYCUBIC_LCD_SERIAL_PORT to be defined in Configuration.h"
+  #elif ANYCUBIC_LCD_SERIAL_PORT == SERIAL_PORT
+    #error "ANYCUBIC_LCD_SERIAL_PORT cannot be the same as SERIAL_PORT. Please update your configuration."
+  #elif defined(SERIAL_PORT_2) && ANYCUBIC_LCD_SERIAL_PORT == SERIAL_PORT_2
+    #error "ANYCUBIC_LCD_SERIAL_PORT cannot be the same as SERIAL_PORT_2. Please update your configuration."
+  #endif
+  #define ANYCUBIC_LCD_SERIAL anycubicLcdSerial
+#endif
+
+/**
  * FYSETC Mini 12864 RGB backlighting required
  */
 #if EITHER(FYSETC_MINI_12864_1_2, FYSETC_MINI_12864_2_0) && DISABLED(RGB_LED)

Marlin/src/lcd/extui/malyan_lcd.cpp

@@ -45,7 +45,7 @@
 
 #if ENABLED(MALYAN_LCD)
 
-#define DEBUG_MALYAN_LCD
+//#define DEBUG_MALYAN_LCD
 
 #include "ui_api.h"
 
@@ -61,10 +61,6 @@
 #define DEBUG_OUT ENABLED(DEBUG_MALYAN_LCD)
 #include "../../core/debug_out.h"
 
-// On the Malyan M200, this will be Serial1. On a RAMPS board,
-// it might not be.
-#define LCD_SERIAL Serial1
-
 // This is based on longest sys command + a filename, plus some buffer
 // in case we encounter some data we don't recognize
 // There is no evidence a line will ever be this long, but better safe than sorry

Marlin/src/pins/stm32f1/pins_BTT_SKR_E3_DIP.h

@@ -117,10 +117,10 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial1
-  //#define Y_HARDWARE_SERIAL  Serial1
-  //#define Z_HARDWARE_SERIAL  Serial1
-  //#define E0_HARDWARE_SERIAL Serial1
+  //#define X_HARDWARE_SERIAL  MSerial1
+  //#define Y_HARDWARE_SERIAL  MSerial1
+  //#define Z_HARDWARE_SERIAL  MSerial1
+  //#define E0_HARDWARE_SERIAL MSerial1
 
   //
   // Software serial

Marlin/src/pins/stm32f1/pins_BTT_SKR_MINI_E3_V1_0.h

@@ -30,8 +30,8 @@
  * Hardware serial communication ports.
  */
 #if HAS_TMC_UART
-  #define X_HARDWARE_SERIAL  Serial4
-  #define Y_HARDWARE_SERIAL  Serial4
-  #define Z_HARDWARE_SERIAL  Serial4
-  #define E0_HARDWARE_SERIAL Serial4
+  #define X_HARDWARE_SERIAL  MSerial4
+  #define Y_HARDWARE_SERIAL  MSerial4
+  #define Z_HARDWARE_SERIAL  MSerial4
+  #define E0_HARDWARE_SERIAL MSerial4
 #endif

Marlin/src/pins/stm32f1/pins_BTT_SKR_MINI_E3_V2_0.h

@@ -52,8 +52,8 @@
  * Hardware serial communication ports.
  */
 #if HAS_TMC_UART
-  #define X_HARDWARE_SERIAL  Serial4
-  #define Y_HARDWARE_SERIAL  Serial4
-  #define Z_HARDWARE_SERIAL  Serial4
-  #define E0_HARDWARE_SERIAL Serial4
+  #define X_HARDWARE_SERIAL  MSerial4
+  #define Y_HARDWARE_SERIAL  MSerial4
+  #define Z_HARDWARE_SERIAL  MSerial4
+  #define E0_HARDWARE_SERIAL MSerial4
 #endif

Marlin/src/pins/stm32f1/pins_FYSETC_AIO_II.h

@@ -93,10 +93,10 @@
   //
   // Hardware serial with switch
   //
-  #define X_HARDWARE_SERIAL  Serial1
-  #define Y_HARDWARE_SERIAL  Serial1
-  #define Z_HARDWARE_SERIAL  Serial1
-  #define E0_HARDWARE_SERIAL Serial1
+  #define X_HARDWARE_SERIAL  MSerial1
+  #define Y_HARDWARE_SERIAL  MSerial1
+  #define Z_HARDWARE_SERIAL  MSerial1
+  #define E0_HARDWARE_SERIAL MSerial1
 
   // The 4xTMC2209 module doesn't have a serial multiplexer and
   // needs to set *_SLAVE_ADDRESS in Configuration_adv.h for X,Y,Z,E0

Marlin/src/pins/stm32f1/pins_MKS_ROBIN.h

@@ -188,17 +188,11 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial1
-  //#define X2_HARDWARE_SERIAL Serial1
-  //#define Y_HARDWARE_SERIAL  Serial1
-  //#define Y2_HARDWARE_SERIAL Serial1
-  //#define Z_HARDWARE_SERIAL  Serial1
-  //#define Z2_HARDWARE_SERIAL Serial1
-  //#define E0_HARDWARE_SERIAL Serial1
-  //#define E1_HARDWARE_SERIAL Serial1
-  //#define E2_HARDWARE_SERIAL Serial1
-  //#define E3_HARDWARE_SERIAL Serial1
-  //#define E4_HARDWARE_SERIAL Serial1
+  //#define X_HARDWARE_SERIAL  MSerial1
+  //#define Y_HARDWARE_SERIAL  MSerial1
+  //#define Z_HARDWARE_SERIAL  MSerial1
+  //#define E0_HARDWARE_SERIAL MSerial1
+  //#define E1_HARDWARE_SERIAL MSerial1
 
   // Unused servo pins may be repurposed with SoftwareSerialM
   //#define X_SERIAL_TX_PIN                 PF8   // SERVO3_PIN -- XS2 - 6

Marlin/src/pins/stm32f1/pins_MKS_ROBIN_E3_common.h

@@ -83,10 +83,10 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial1
-  //#define Y_HARDWARE_SERIAL  Serial1
-  //#define Z_HARDWARE_SERIAL  Serial1
-  //#define E0_HARDWARE_SERIAL Serial1
+  //#define X_HARDWARE_SERIAL  MSerial1
+  //#define Y_HARDWARE_SERIAL  MSerial1
+  //#define Z_HARDWARE_SERIAL  MSerial1
+  //#define E0_HARDWARE_SERIAL MSerial1
 
   //
   // Software serial

Marlin/src/pins/stm32f1/pins_MKS_ROBIN_NANO_V2.h

@@ -132,17 +132,11 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial1
-  //#define X2_HARDWARE_SERIAL Serial1
-  //#define Y_HARDWARE_SERIAL  Serial1
-  //#define Y2_HARDWARE_SERIAL Serial1
-  //#define Z_HARDWARE_SERIAL  Serial1
-  //#define Z2_HARDWARE_SERIAL Serial1
-  //#define E0_HARDWARE_SERIAL Serial1
-  //#define E1_HARDWARE_SERIAL Serial1
-  //#define E2_HARDWARE_SERIAL Serial1
-  //#define E3_HARDWARE_SERIAL Serial1
-  //#define E4_HARDWARE_SERIAL Serial1
+  //#define X_HARDWARE_SERIAL  MSerial1
+  //#define Y_HARDWARE_SERIAL  MSerial1
+  //#define Z_HARDWARE_SERIAL  MSerial1
+  //#define E0_HARDWARE_SERIAL MSerial1
+  //#define E1_HARDWARE_SERIAL MSerial1
 
   //
   // Software serial

Marlin/src/pins/stm32f1/pins_MKS_ROBIN_PRO.h

@@ -125,17 +125,12 @@
    * Hardware serial communication ports.
    * If undefined software serial is used according to the pins below
    */
-  //#define X_HARDWARE_SERIAL  Serial1
-  //#define X2_HARDWARE_SERIAL Serial1
-  //#define Y_HARDWARE_SERIAL  Serial1
-  //#define Y2_HARDWARE_SERIAL Serial1
-  //#define Z_HARDWARE_SERIAL  Serial1
-  //#define Z2_HARDWARE_SERIAL Serial1
-  //#define E0_HARDWARE_SERIAL Serial1
-  //#define E1_HARDWARE_SERIAL Serial1
-  //#define E2_HARDWARE_SERIAL Serial1
-  //#define E3_HARDWARE_SERIAL Serial1
-  //#define E4_HARDWARE_SERIAL Serial1
+  //#define X_HARDWARE_SERIAL  MSerial1
+  //#define Y_HARDWARE_SERIAL  MSerial1
+  //#define Z_HARDWARE_SERIAL  MSerial1
+  //#define E0_HARDWARE_SERIAL MSerial1
+  //#define E1_HARDWARE_SERIAL MSerial1
+  //#define E2_HARDWARE_SERIAL MSerial1
 
   //
   // Software serial

buildroot/tests/malyan_M300-tests

@@ -9,6 +9,7 @@ set -e
 restore_configs
 use_example_configs "delta/Malyan M300"
 opt_disable AUTO_BED_LEVELING_3POINT
+opt_set LCD_SERIAL_PORT 1
 exec_test $1 $2 "Malyan M300 (delta)"
 
 # cleanup