usb and sdcard sharing improvements

* Add traceback after watchdog timeout

Add the cpability to perform a traceback following a watchdog timeout.

* Enhanced hardware SPI

Allow use of either SSP0 or SSP1.
Ensure that no data is left in I/O buffers after calls to enable sharing of SSP hardware.

* Make flash emulation of eeprom the default

Make use of flash for eeprom storage the default. This means that usage of eeprom will not cause USB drive mount/unmount operations.

* Allow sharing of SD card

SD card I/O operations from the USB stack take place in idle loop, rather than at interrupt time. Allowing sharing of the SPI bus.

New configuration options to allow usage of the SD card to be specified.

* Fix problem with hardware SPI pins

Marlin/src/HAL/HAL_LPC1768/DebugMonitor_LPC1768.cpp

@@ -0,0 +1,318 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (C) 2016 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifdef TARGET_LPC1768
+
+#include "../../core/macros.h"
+#include "../../core/serial.h"
+#include <stdarg.h>
+
+#include "../shared/backtrace/unwinder.h"
+#include "../shared/backtrace/unwmemaccess.h"
+#include "watchdog.h"
+#include <debug_frmwrk.h>
+
+
+// Debug monitor that dumps to the Programming port all status when
+// an exception or WDT timeout happens - And then resets the board
+
+// All the Monitor routines must run with interrupts disabled and
+// under an ISR execution context. That is why we cannot reuse the
+// Serial interrupt routines or any C runtime, as we don't know the
+// state we are when running them
+
+// A SW memory barrier, to ensure GCC does not overoptimize loops
+#define sw_barrier() __asm__ volatile("": : :"memory");
+
+// (re)initialize UART0 as a monitor output to 250000,n,8,1
+static void TXBegin(void) {
+}
+
+// Send character through UART with no interrupts
+static void TX(char c) {
+  _DBC(c);
+}
+
+// Send String through UART
+static void TX(const char* s) {
+  while (*s) TX(*s++);
+}
+
+static void TXDigit(uint32_t d) {
+  if (d < 10) TX((char)(d+'0'));
+  else if (d < 16) TX((char)(d+'A'-10));
+  else TX('?');
+}
+
+// Send Hex number thru UART
+static void TXHex(uint32_t v) {
+  TX("0x");
+  for (uint8_t i = 0; i < 8; i++, v <<= 4)
+    TXDigit((v >> 28) & 0xF);
+}
+
+// Send Decimal number thru UART
+static void TXDec(uint32_t v) {
+  if (!v) {
+    TX('0');
+    return;
+  }
+
+  char nbrs[14];
+  char *p = &nbrs[0];
+  while (v != 0) {
+    *p++ = '0' + (v % 10);
+    v /= 10;
+  }
+  do {
+    p--;
+    TX(*p);
+  } while (p != &nbrs[0]);
+}
+
+// Dump a backtrace entry
+static bool UnwReportOut(void* ctx, const UnwReport* bte) {
+  int* p = (int*)ctx;
+
+  (*p)++;
+  TX('#'); TXDec(*p); TX(" : ");
+  TX(bte->name?bte->name:"unknown"); TX('@'); TXHex(bte->function);
+  TX('+'); TXDec(bte->address - bte->function);
+  TX(" PC:");TXHex(bte->address); TX('\n');
+  return true;
+}
+
+#ifdef UNW_DEBUG
+  void UnwPrintf(const char* format, ...) {
+    char dest[256];
+    va_list argptr;
+    va_start(argptr, format);
+    vsprintf(dest, format, argptr);
+    va_end(argptr);
+    TX(&dest[0]);
+  }
+#endif
+
+/* Table of function pointers for passing to the unwinder */
+static const UnwindCallbacks UnwCallbacks = {
+  UnwReportOut,
+  UnwReadW,
+  UnwReadH,
+  UnwReadB
+  #if defined(UNW_DEBUG)
+   ,UnwPrintf
+  #endif
+};
+
+
+/**
+ * HardFaultHandler_C:
+ * This is called from the HardFault_HandlerAsm with a pointer the Fault stack
+ * as the parameter. We can then read the values from the stack and place them
+ * into local variables for ease of reading.
+ * We then read the various Fault Status and Address Registers to help decode
+ * cause of the fault.
+ * The function ends with a BKPT instruction to force control back into the debugger
+ */
+extern "C"
+void HardFault_HandlerC(unsigned long *sp, unsigned long lr, unsigned long cause) {
+
+  static const char* causestr[] = {
+    "NMI","Hard","Mem","Bus","Usage","Debug","WDT","RSTC"
+  };
+
+  UnwindFrame btf;
+
+  // Dump report to the Programming port (interrupts are DISABLED)
+  TXBegin();
+  TX("\n\n## Software Fault detected ##\n");
+  TX("Cause: "); TX(causestr[cause]); TX('\n');
+
+  TX("R0   : "); TXHex(((unsigned long)sp[0])); TX('\n');
+  TX("R1   : "); TXHex(((unsigned long)sp[1])); TX('\n');
+  TX("R2   : "); TXHex(((unsigned long)sp[2])); TX('\n');
+  TX("R3   : "); TXHex(((unsigned long)sp[3])); TX('\n');
+  TX("R12  : "); TXHex(((unsigned long)sp[4])); TX('\n');
+  TX("LR   : "); TXHex(((unsigned long)sp[5])); TX('\n');
+  TX("PC   : "); TXHex(((unsigned long)sp[6])); TX('\n');
+  TX("PSR  : "); TXHex(((unsigned long)sp[7])); TX('\n');
+
+  // Configurable Fault Status Register
+  // Consists of MMSR, BFSR and UFSR
+  TX("CFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED28)))); TX('\n');
+
+  // Hard Fault Status Register
+  TX("HFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED2C)))); TX('\n');
+
+  // Debug Fault Status Register
+  TX("DFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED30)))); TX('\n');
+
+  // Auxiliary Fault Status Register
+  TX("AFSR : "); TXHex((*((volatile unsigned long *)(0xE000ED3C)))); TX('\n');
+
+  // Read the Fault Address Registers. These may not contain valid values.
+  // Check BFARVALID/MMARVALID to see if they are valid values
+  // MemManage Fault Address Register
+  TX("MMAR : "); TXHex((*((volatile unsigned long *)(0xE000ED34)))); TX('\n');
+
+  // Bus Fault Address Register
+  TX("BFAR : "); TXHex((*((volatile unsigned long *)(0xE000ED38)))); TX('\n');
+
+  TX("ExcLR: "); TXHex(lr); TX('\n');
+  TX("ExcSP: "); TXHex((unsigned long)sp); TX('\n');
+
+  btf.sp = ((unsigned long)sp) + 8*4; // The original stack pointer
+  btf.fp = btf.sp;
+  btf.lr = ((unsigned long)sp[5]);
+  btf.pc = ((unsigned long)sp[6]) | 1; // Force Thumb, as CORTEX only support it
+
+  // Perform a backtrace
+  TX("\nBacktrace:\n\n");
+  int ctr = 0;
+  UnwindStart(&btf, &UnwCallbacks, &ctr);
+
+  // Disable all NVIC interrupts
+  NVIC->ICER[0] = 0xFFFFFFFF;
+  NVIC->ICER[1] = 0xFFFFFFFF;
+
+  // Relocate VTOR table to default position
+  SCB->VTOR = 0;
+
+  // Clear cause of reset to prevent entering smoothie bootstrap
+  HAL_clear_reset_source();
+  // Restart watchdog
+  //WDT_Restart(WDT);
+  watchdog_init();
+
+  // Reset controller
+  NVIC_SystemReset();
+
+  while(1) { watchdog_init(); }
+}
+
+extern "C" {
+__attribute__((naked)) void NMI_Handler(void) {
+  __asm__ __volatile__ (
+    ".syntax unified" "\n\t"
+    A("tst lr, #4")
+    A("ite eq")
+    A("mrseq r0, msp")
+    A("mrsne r0, psp")
+    A("mov r1,lr")
+    A("mov r2,#0")
+    A("b HardFault_HandlerC")
+  );
+}
+
+__attribute__((naked)) void HardFault_Handler(void) {
+  __asm__ __volatile__ (
+    ".syntax unified" "\n\t"
+    A("tst lr, #4")
+    A("ite eq")
+    A("mrseq r0, msp")
+    A("mrsne r0, psp")
+    A("mov r1,lr")
+    A("mov r2,#1")
+    A("b HardFault_HandlerC")
+  );
+}
+
+__attribute__((naked)) void MemManage_Handler(void) {
+  __asm__ __volatile__ (
+    ".syntax unified" "\n\t"
+    A("tst lr, #4")
+    A("ite eq")
+    A("mrseq r0, msp")
+    A("mrsne r0, psp")
+    A("mov r1,lr")
+    A("mov r2,#2")
+    A("b HardFault_HandlerC")
+  );
+}
+
+__attribute__((naked)) void BusFault_Handler(void) {
+  __asm__ __volatile__ (
+    ".syntax unified" "\n\t"
+    A("tst lr, #4")
+    A("ite eq")
+    A("mrseq r0, msp")
+    A("mrsne r0, psp")
+    A("mov r1,lr")
+    A("mov r2,#3")
+    A("b HardFault_HandlerC")
+  );
+}
+
+__attribute__((naked)) void UsageFault_Handler(void) {
+  __asm__ __volatile__ (
+    ".syntax unified" "\n\t"
+    A("tst lr, #4")
+    A("ite eq")
+    A("mrseq r0, msp")
+    A("mrsne r0, psp")
+    A("mov r1,lr")
+    A("mov r2,#4")
+    A("b HardFault_HandlerC")
+  );
+}
+
+__attribute__((naked)) void DebugMon_Handler(void) {
+  __asm__ __volatile__ (
+    ".syntax unified" "\n\t"
+    A("tst lr, #4")
+    A("ite eq")
+    A("mrseq r0, msp")
+    A("mrsne r0, psp")
+    A("mov r1,lr")
+    A("mov r2,#5")
+    A("b HardFault_HandlerC")
+  );
+}
+
+/* This is NOT an exception, it is an interrupt handler - Nevertheless, the framing is the same */
+__attribute__((naked)) void WDT_IRQHandler(void) {
+  __asm__ __volatile__ (
+    ".syntax unified" "\n\t"
+    A("tst lr, #4")
+    A("ite eq")
+    A("mrseq r0, msp")
+    A("mrsne r0, psp")
+    A("mov r1,lr")
+    A("mov r2,#6")
+    A("b HardFault_HandlerC")
+  );
+}
+
+__attribute__((naked)) void RSTC_Handler(void) {
+  __asm__ __volatile__ (
+    ".syntax unified" "\n\t"
+    A("tst lr, #4")
+    A("ite eq")
+    A("mrseq r0, msp")
+    A("mrsne r0, psp")
+    A("mov r1,lr")
+    A("mov r2,#7")
+    A("b HardFault_HandlerC")
+  );
+}
+}
+#endif // ARDUINO_ARCH_SAM

Marlin/src/HAL/HAL_LPC1768/HAL.h

@@ -152,4 +152,7 @@ using FilteredADC = LPC176x::ADC<ADC_LOWPASS_K_VALUE, ADC_MEDIAN_FILTER_SIZE>;
 // Parse a G-code word into a pin index
 int16_t PARSED_PIN_INDEX(const char code, const int16_t dval);
 
+#define HAL_IDLETASK 1
+void HAL_idletask(void);
+
 #endif // _HAL_LPC1768_H_

Marlin/src/HAL/HAL_LPC1768/HAL_spi.cpp

@@ -49,7 +49,6 @@
 #ifdef TARGET_LPC1768
 
 #include "../../inc/MarlinConfig.h"
-
 // --------------------------------------------------------------------------
 // Includes
 // --------------------------------------------------------------------------
@@ -59,7 +58,6 @@
 // --------------------------------------------------------------------------
 // Public functions
 // --------------------------------------------------------------------------
-
 #if ENABLED(LPC_SOFTWARE_SPI)
 
   #include "SoftwareSPI.h"
@@ -127,8 +125,25 @@
   #include <lpc17xx_ssp.h>
   #include <lpc17xx_clkpwr.h>
 
-  void spiBegin() {  // setup SCK, MOSI & MISO pins for SSP0
+  // decide which HW SPI device to use
+  #ifndef LPC_HW_SPI_DEV
+    #if (SCK_PIN == P0_07 && MISO_PIN == P0_08 && MOSI_PIN == P0_09)
+      #define LPC_HW_SPI_DEV 1
+    #else
+      #if (SCK_PIN == P0_15 && MISO_PIN == P0_17 && MOSI_PIN == P0_18)
+        #define LPC_HW_SPI_DEV 0
+      #else
+        #error "Invalid pins selected for hardware SPI"
+      #endif
+    #endif
+  #endif
+  #if (LPC_HW_SPI_DEV == 0)
+    #define LPC_SSPn LPC_SSP0
+  #else
+    #define LPC_SSPn LPC_SSP1
+  #endif
 
+  void spiBegin() {  // setup SCK, MOSI & MISO pins for SSP0
     PINSEL_CFG_Type PinCfg;  // data structure to hold init values
     PinCfg.Funcnum = 2;
     PinCfg.OpenDrain = 0;
@@ -147,10 +162,13 @@
     PinCfg.Portnum = LPC1768_PIN_PORT(MOSI_PIN);
     PINSEL_ConfigPin(&PinCfg);
     SET_OUTPUT(MOSI_PIN);
+    // divide PCLK by 2 for SSP0
+    CLKPWR_SetPCLKDiv(LPC_HW_SPI_DEV == 0 ? CLKPWR_PCLKSEL_SSP0 : CLKPWR_PCLKSEL_SSP1, CLKPWR_PCLKSEL_CCLK_DIV_2);
+    spiInit(0);
+    SSP_Cmd(LPC_SSPn, ENABLE);  // start SSP running
   }
 
   void spiInit(uint8_t spiRate) {
-    SSP_Cmd(LPC_SSP0, DISABLE); // Disable SSP0 before changing rate
     // table to convert Marlin spiRates (0-5 plus default) into bit rates
     uint32_t Marlin_speed[7]; // CPSR is always 2
     Marlin_speed[0] = 8333333; //(SCR:  2)  desired: 8,000,000  actual: 8,333,333  +4.2%  SPI_FULL_SPEED
@@ -160,33 +178,32 @@
     Marlin_speed[4] =  500000; //(SCR: 49)  desired:   500,000  actual:   500,000         SPI_SPEED_5
     Marlin_speed[5] =  250000; //(SCR: 99)  desired:   250,000  actual:   250,000         SPI_SPEED_6
     Marlin_speed[6] =  125000; //(SCR:199)  desired:   125,000  actual:   125,000         Default from HAL.h
-
-    // divide PCLK by 2 for SSP0
-    CLKPWR_SetPCLKDiv(CLKPWR_PCLKSEL_SSP0, CLKPWR_PCLKSEL_CCLK_DIV_2);
-
     // setup for SPI mode
     SSP_CFG_Type HW_SPI_init; // data structure to hold init values
     SSP_ConfigStructInit(&HW_SPI_init);  // set values for SPI mode
     HW_SPI_init.ClockRate = Marlin_speed[MIN(spiRate, 6)]; // put in the specified bit rate
-    SSP_Init(LPC_SSP0, &HW_SPI_init);  // puts the values into the proper bits in the SSP0 registers
+    HW_SPI_init.Mode |= SSP_CR1_SSP_EN;
+    SSP_Init(LPC_SSPn, &HW_SPI_init);  // puts the values into the proper bits in the SSP0 registers
+  }
+
 
-    SSP_Cmd(LPC_SSP0, ENABLE);  // start SSP0 running
+  static uint8_t doio(uint8_t b) {
+    /* send and receive a single byte */
+    SSP_SendData(LPC_SSPn, b & 0x00FF);
+    while (SSP_GetStatus(LPC_SSPn, SSP_STAT_BUSY));  // wait for it to finish
+    return SSP_ReceiveData(LPC_SSPn) & 0x00FF;
   }
 
   void spiSend(uint8_t b) {
-    while (!SSP_GetStatus(LPC_SSP0, SSP_STAT_TXFIFO_NOTFULL));   // wait for room in the buffer
-    SSP_SendData(LPC_SSP0, b & 0x00FF);
-    while (SSP_GetStatus(LPC_SSP0, SSP_STAT_BUSY));  // wait for it to finish
+    doio(b);
   }
 
 
   void spiSend(const uint8_t* buf, size_t n) {
     if (n == 0) return;
     for (uint16_t i = 0; i < n; i++) {
-      while (!SSP_GetStatus(LPC_SSP0, SSP_STAT_TXFIFO_NOTFULL));   // wait for room in the buffer
-      SSP_SendData(LPC_SSP0, buf[i] & 0x00FF);
+      doio(buf[i]);
     }
-    while (SSP_GetStatus(LPC_SSP0, SSP_STAT_BUSY));  // wait for it to finish
   }
 
   void spiSend(uint32_t chan, byte b) {
@@ -195,17 +212,9 @@
   void spiSend(uint32_t chan, const uint8_t* buf, size_t n) {
   }
 
-  static uint8_t get_one_byte() {
-    // send a dummy byte so can clock in receive data
-    SSP_SendData(LPC_SSP0,0x00FF);
-    while (SSP_GetStatus(LPC_SSP0, SSP_STAT_BUSY));  // wait for it to finish
-    return SSP_ReceiveData(LPC_SSP0) & 0x00FF;
-  }
-
   // Read single byte from SPI
   uint8_t spiRec() {
-    while (SSP_GetStatus(LPC_SSP0, SSP_STAT_RXFIFO_NOTEMPTY) || SSP_GetStatus(LPC_SSP0, SSP_STAT_BUSY)) SSP_ReceiveData(LPC_SSP0);  //flush the receive buffer
-    return get_one_byte();
+    return doio(0xff);
   }
 
   uint8_t spiRec(uint32_t chan) {
@@ -214,22 +223,25 @@
 
   // Read from SPI into buffer
   void spiRead(uint8_t*buf, uint16_t nbyte) {
-    while (SSP_GetStatus(LPC_SSP0, SSP_STAT_RXFIFO_NOTEMPTY) || SSP_GetStatus(LPC_SSP0, SSP_STAT_BUSY)) SSP_ReceiveData(LPC_SSP0);  //flush the receive buffer
     if (nbyte == 0) return;
     for (int i = 0; i < nbyte; i++) {
-      buf[i] = get_one_byte();
+      buf[i] = doio(0xff);
     }
   }
 
   static uint8_t spiTransfer(uint8_t b) {
-    while (SSP_GetStatus(LPC_SSP0, SSP_STAT_RXFIFO_NOTEMPTY) || SSP_GetStatus(LPC_SSP0, SSP_STAT_BUSY)) SSP_ReceiveData(LPC_SSP0);  //flush the receive buffer
-    SSP_SendData(LPC_SSP0, b);  // send the byte
-    while (SSP_GetStatus(LPC_SSP0, SSP_STAT_BUSY));  // wait for it to finish
-    return SSP_ReceiveData(LPC_SSP0) & 0x00FF;
+    return doio(b);
   }
 
   // Write from buffer to SPI
   void spiSendBlock(uint8_t token, const uint8_t* buf) {
+    uint8_t response;
+    response = spiTransfer(token);
+
+    for (uint16_t i = 0; i < 512; i++) {
+      response = spiTransfer(buf[i]);
+    }
+    UNUSED(response);
   }
 
   /** Begin SPI transaction, set clock, bit order, data mode */
@@ -270,4 +282,3 @@ uint16_t SPIClass::transfer16(uint16_t data) {
 SPIClass SPI;
 
 #endif // TARGET_LPC1768
-

Marlin/src/HAL/HAL_LPC1768/fastio.h

@@ -39,19 +39,19 @@
 
 #define USEABLE_HARDWARE_PWM(pin) useable_hardware_PWM(pin)
 
-#define LPC_PIN(pin)            (gpio_pin(pin))
-#define LPC_GPIO(port)          (gpio_port(port))
+#define LPC_PIN(pin)            gpio_pin(pin)
+#define LPC_GPIO(port)          gpio_port(port)
 
-#define SET_DIR_INPUT(IO)       (gpio_set_input(IO))
-#define SET_DIR_OUTPUT(IO)      (gpio_set_output(IO))
+#define SET_DIR_INPUT(IO)       gpio_set_input(IO)
+#define SET_DIR_OUTPUT(IO)      gpio_set_output(IO)
 
-#define SET_MODE(IO, mode)      (pinMode(IO, mode))
+#define SET_MODE(IO, mode)      pinMode(IO, mode)
 
-#define WRITE_PIN_SET(IO)       (gpio_set(IO))
-#define WRITE_PIN_CLR(IO)       (gpio_clear(IO))
+#define WRITE_PIN_SET(IO)       gpio_set(IO)
+#define WRITE_PIN_CLR(IO)       gpio_clear(IO)
 
-#define READ_PIN(IO)            (gpio_get(IO))
-#define WRITE_PIN(IO,V)         (gpio_set(IO, V))
+#define READ_PIN(IO)            gpio_get(IO)
+#define WRITE_PIN(IO,V)         gpio_set(IO, V)
 
 /**
  * Magic I/O routines

Marlin/src/HAL/HAL_LPC1768/main.cpp

@@ -9,7 +9,13 @@
 #include <usb/cdcuser.h>
 #include <usb/mscuser.h>
 #include <CDCSerial.h>
+#include <usb/mscuser.h>
+
+extern "C" {
+  #include <debug_frmwrk.h>
+}
 
+#include "../../sd/cardreader.h"
 #include "../../inc/MarlinConfig.h"
 #include "HAL.h"
 #include "HAL_timers.h"
@@ -41,15 +47,28 @@ void HAL_init() {
       delay(100);
     }
   #endif
-
-  (void)MSC_SD_Init(0);
-
-  USB_Init();
+  //debug_frmwrk_init();
+  //_DBG("\n\nDebug running\n");
+  // Initialise the SD card chip select pins as soon as possible
+  #ifdef SS_PIN
+    digitalWrite(SS_PIN, HIGH);
+    pinMode(SS_PIN, OUTPUT);
+  #endif
+  #ifdef ONBOARD_SD_CS
+    digitalWrite(ONBOARD_SD_CS, HIGH);
+    pinMode(ONBOARD_SD_CS, OUTPUT);
+  #endif
+  USB_Init();                               // USB Initialization
+  USB_Connect(FALSE);                       // USB clear connection
+  delay(1000);                              // Give OS time to notice
   USB_Connect(TRUE);
-
+  #ifndef USB_SD_DISABLED
+    MSC_SD_Init(0);                         // Enable USB SD card access
+  #endif
   const uint32_t usb_timeout = millis() + 2000;
   while (!USB_Configuration && PENDING(millis(), usb_timeout)) {
     delay(50);
+    HAL_idletask();
     #if PIN_EXISTS(LED)
       TOGGLE(LED_PIN);     // Flash quickly during USB initialization
     #endif
@@ -68,4 +87,23 @@ void HAL_init() {
   LPC1768_PWM_init();
 }
 
+// HAL idle task
+void HAL_idletask(void) {
+  #if ENABLED(SDSUPPORT) && defined(SHARED_SD_CARD)
+    // If Marlin is using the SD card we need to lock it to prevent access from
+    // a PC via USB.
+    // Other HALs use IS_SD_PRINTING and IS_SD_FILE_OPEN to check for access but
+    // this will not reliably detect delete operations. To be safe we will lock
+    // the disk if Marlin has it mounted. Unfortuately there is currently no way
+    // to unmount the disk from the LCD menu.
+    // if (IS_SD_PRINTING || IS_SD_FILE_OPEN)
+    if (card.cardOK)
+      MSC_Aquire_Lock();
+    else
+      MSC_Release_Lock();
+  #endif
+  // Perform USB stack housekeeping
+  MSC_RunDeferredCommands();
+}
+
 #endif // TARGET_LPC1768

Marlin/src/HAL/HAL_LPC1768/persistent_store_api.h

@@ -21,4 +21,4 @@
  */
 #include "../shared/persistent_store_api.h"
 
-//#define FLASH_EEPROM
+#define FLASH_EEPROM

Marlin/src/HAL/HAL_LPC1768/persistent_store_flash.cpp

@@ -116,7 +116,7 @@ bool PersistentStore::access_finish() {
 }
 
 bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
-  for (int i = 0; i < size; i++) ram_eeprom[pos + i] = value[i];
+  for (size_t i = 0; i < size; i++) ram_eeprom[pos + i] = value[i];
   eeprom_dirty = true;
   crc16(crc, value, size);
   pos += size;
@@ -125,7 +125,7 @@ bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, ui
 
 bool PersistentStore::read_data(int &pos, uint8_t* value, size_t size, uint16_t *crc, const bool writing/*=true*/) {
   const uint8_t * const buff = writing ? &value[0] : &ram_eeprom[pos];
-  if (writing) for (int i = 0; i < size; i++) value[i] = ram_eeprom[pos + i];
+  if (writing) for (size_t i = 0; i < size; i++) value[i] = ram_eeprom[pos + i];
   crc16(crc, buff, size);
   pos += size;
   return false;  // return true for any error

Marlin/src/HAL/HAL_LPC1768/spi_pins.h

@@ -50,7 +50,8 @@
 #ifndef SS_PIN
   #define SS_PIN            P1_23
 #endif
-#ifndef SDSS
+#if !defined(SDSS) || SDSS == P_NC // get defaulted in pins.h
+  #undef SDSS
   #define SDSS              SS_PIN
 #endif
 

Marlin/src/HAL/HAL_LPC1768/u8g/u8g_com_HAL_LPC1768_st7920_sw_spi.cpp

@@ -63,6 +63,7 @@
 #include "SoftwareSPI.h"
 #include "../../shared/Delay.h"
 
+#undef SPI_SPEED
 #define SPI_SPEED 3  // About 1 MHz
 
 static pin_t SCK_pin_ST7920_HAL, MOSI_pin_ST7920_HAL_HAL;

Marlin/src/HAL/HAL_LPC1768/u8g/u8g_com_HAL_LPC1768_sw_spi.cpp

@@ -62,6 +62,7 @@
 #include <U8glib.h>
 #include "SoftwareSPI.h"
 
+#undef SPI_SPEED
 #define SPI_SPEED 2  // About 2 MHz
 
 static uint8_t SPI_speed = 0;

Marlin/src/HAL/HAL_LPC1768/watchdog.cpp

@@ -30,7 +30,29 @@
 #include "watchdog.h"
 
 void watchdog_init(void) {
-  WDT_Init(WDT_CLKSRC_IRC, WDT_MODE_RESET);
+  #if ENABLED(WATCHDOG_RESET_MANUAL)
+    // We enable the watchdog timer, but only for the interrupt.
+
+    // Configure WDT to only trigger an interrupt
+    // Disable WDT interrupt (just in case, to avoid triggering it!)
+    NVIC_DisableIRQ(WDT_IRQn);
+
+    // We NEED memory barriers to ensure Interrupts are actually disabled!
+    // ( https://dzone.com/articles/nvic-disabling-interrupts-on-arm-cortex-m-and-the )
+    __DSB();
+    __ISB();
+
+    // Configure WDT to only trigger an interrupt
+    // Initialize WDT with the given parameters
+    WDT_Init(WDT_CLKSRC_IRC, WDT_MODE_INT_ONLY);
+
+    // Configure and enable WDT interrupt.
+    NVIC_ClearPendingIRQ(WDT_IRQn);
+    NVIC_SetPriority(WDT_IRQn, 0); // Use highest priority, so we detect all kinds of lockups
+    NVIC_EnableIRQ(WDT_IRQn);
+  #else
+    WDT_Init(WDT_CLKSRC_IRC, WDT_MODE_RESET);
+  #endif
   WDT_Start(WDT_TIMEOUT);
 }
 

Marlin/src/pins/pins.h

@@ -299,19 +299,19 @@
 #elif MB(AZSMZ_MINI)
   #include "pins_AZSMZ_MINI.h"        // LPC1768                                    env:LPC1768
 #elif MB(AZTEEG_X5_GT)
-  #include "pins_AZTEEG_X5_GT.h"      // LPC1769                                    env:LPC1768
+  #include "pins_AZTEEG_X5_GT.h"      // LPC1769                                    env:LPC1769
 #elif MB(AZTEEG_X5_MINI_WIFI)
-  #include "pins_AZTEEG_X5_MINI_WIFI.h" // LPC1769                                  env:LPC1768
+  #include "pins_AZTEEG_X5_MINI_WIFI.h" // LPC1769                                  env:LPC1769
 #elif MB(BIQU_BQ111_A4)
   #include "pins_BIQU_BQ111_A4.h"     // LPC1768                                    env:LPC1768
 #elif MB(SELENA_COMPACT)
   #include "pins_SELENA_COMPACT.h"    // LPC1768                                    env:LPC1768
 #elif MB(COHESION3D_REMIX)
-  #include "pins_COHESION3D_REMIX.h"  // LPC1769                                    env:LPC1768
+  #include "pins_COHESION3D_REMIX.h"  // LPC1769                                    env:LPC1769
 #elif MB(COHESION3D_MINI)
-  #include "pins_COHESION3D_MINI.h"   // LPC1769                                    env:LPC1768
+  #include "pins_COHESION3D_MINI.h"   // LPC1769                                    env:LPC1769
 #elif MB(SMOOTHIEBOARD)
-  #include "pins_SMOOTHIEBOARD.h"     // LPC1769                                    env:LPC1768
+  #include "pins_SMOOTHIEBOARD.h"     // LPC1769                                    env:LPC1769
 
 //
 // Other 32-bit Boards

Marlin/src/pins/pins_MKS_SBASE.h

@@ -141,8 +141,6 @@
 // Misc. Functions
 //
 #define PS_ON_PIN          P0_25 //TH3 Connector
-#define LPC_SOFTWARE_SPI  // MKS_SBASE needs a software SPI because the
-                          // selected pins are not on a hardware SPI controller
 
 /**
  * Smart LCD adapter
@@ -185,14 +183,77 @@
 #define ENET_TXD0          P1_00   // J12-11
 #define ENET_TXD1          P1_01   // J12-12
 
-// A custom cable is needed. See the README file in the
-// Marlin\src\config\examples\Mks\Sbase directory
 
-#define SCK_PIN            P1_22   // J8-2 (moved from EXP2 P0.7)
-#define MISO_PIN           P1_23   // J8-3 (moved from EXP2 P0.8)
-#define MOSI_PIN           P2_12   // J8-4 (moved from EXP2 P0.5)
-#define SS_PIN             P0_28
-#define SDSS               P0_06
+/*
+ * The SBase can share the on-board SD card with a PC via USB the following
+ * definitions control this feature:
+ */
+//#define USB_SD_DISABLED
+#define USB_SD_ONBOARD
+
+/*
+ * There are a number of configurations available for the SBase SD card reader.
+ * A custom cable can be used to allow access to the LCD based SD card.
+ * A standard cable can be used for access to the LCD SD card (but no SD detect).
+ * The onboard SD card can be used and optionally shared with a PC via USB.
+ */
+
+//#define SBASE_SD_CUSTOM_CABLE // Use a custom cable to access the SD
+//#define SBASE_SD_LCD          // Use the SD drive attached to the LCD
+#define SBASE_SD_ONBOARD        // Use the SD drive on the control board
+
+#ifdef SBASE_SD_CUSTOM_CABLE
+  /**
+   * A custom cable is needed. See the README file in the
+   * Marlin\src\config\examples\Mks\Sbase directory
+   * P0.27 is on EXP2 and the on-board SD card's socket. That means it can't be
+   * used as the SD_DETECT for the LCD's SD card.
+   *
+   * The best solution is to use the custom cable to connect the LCD's SD_DETECT
+   * to a pin NOT on EXP2.
+   *
+   * If you can't find a pin to use for the LCD's SD_DETECT then comment out
+   * SD_DETECT_PIN entirely and remove that wire from the the custom cable.
+   */
+  #define SD_DETECT_PIN      P2_11   // J8-5 (moved from EXP2 P0.27)
+  #define SCK_PIN            P1_22   // J8-2 (moved from EXP2 P0.7)
+  #define MISO_PIN           P1_23   // J8-3 (moved from EXP2 P0.8)
+  #define MOSI_PIN           P2_12   // J8-4 (moved from EXP2 P0.9)
+  #define SS_PIN             P0_28   // Chip select for SD card used by Marlin
+  #define ONBOARD_SD_CS      P0_06   // Chip select for "System" SD card
+  #define LPC_SOFTWARE_SPI  // With a custom cable we need software SPI because the
+                            // selected pins are not on a hardware SPI controller
+#endif
+
+#ifdef SBASE_SD_LCD
+  // use standard cable and header, SPI and SD detect sre shared with on-board SD card
+  // hardware SPI is used for both SD cards. The detect pin is shred between the
+  // LCD and onboard SD readers so we disable it.
+  #define SD_DETECT_PIN      P0_27
+  #undef SD_DETECT_PIN
+  #define SCK_PIN            P0_07
+  #define MISO_PIN           P0_08
+  #define MOSI_PIN           P0_09
+  #define SS_PIN             P0_28   // Chip select for SD card used by Marlin
+  #define ONBOARD_SD_CS      P0_06   // Chip select for "System" SD card
+#endif
+
+#ifdef SBASE_SD_ONBOARD
+  // The external SD card is not used. Hardware SPI is used to access the card.
+  #ifdef USB_SD_ONBOARD
+    // When sharing the SD card with a PC we want the menu options to
+    // mount/unmount the card and refresh it. So we disable card detect.
+    #define SHARED_SD_CARD
+    #undef SD_DETECT_PIN
+  #else
+    #define SD_DETECT_PIN      P0_27
+  #endif
+  #define SCK_PIN            P0_07
+  #define MISO_PIN           P0_08
+  #define MOSI_PIN           P0_09
+  #define SS_PIN             P0_06   // Chip select for SD card used by Marlin
+  #define ONBOARD_SD_CS      P0_06   // Chip select for "System" SD card
+#endif
 
 /**
  * Example for trinamic drivers using the J8 connector on MKs Sbase.
@@ -238,18 +299,6 @@
 #endif
 
 /**
- * P0.27 is on EXP2 and the on-board SD card's socket. That means it can't be
- * used as the SD_DETECT for the LCD's SD card.
- *
- * The best solution is to use the custom cable to connect the LCD's SD_DETECT
- * to a pin NOT on EXP2.
- *
- * If you can't find a pin to use for the LCD's SD_DETECT then comment out
- * SD_DETECT_PIN entirely and remove that wire from the the custom cable.
- */
-#define SD_DETECT_PIN      P2_11   // J8-5 (moved from EXP2 P0.27)
-
-/**
  *  PWMs
  *
  *  There are 6 PWMs.  Each PWM can be assigned to one of two pins.

platformio.ini

@@ -153,6 +153,9 @@ platform          = https://github.com/p3p/pio-nxplpc-arduino-lpc176x/archive/ma
 framework         = arduino
 board             = nxp_lpc1768
 build_flags       = -DTARGET_LPC1768 -DU8G_HAL_LINKS -IMarlin/src/HAL/HAL_LPC1768/include -IMarlin/src/HAL/HAL_LPC1768/u8g ${common.build_flags}
+# debug options for backtrace
+#  -funwind-tables
+#  -mpoke-function-name
 lib_ldf_mode      = off
 extra_scripts     = Marlin/src/HAL/HAL_LPC1768/upload_extra_script.py
 src_filter        = ${common.default_src_filter} +<src/HAL/HAL_LPC1768>
@@ -165,6 +168,9 @@ platform          = https://github.com/p3p/pio-nxplpc-arduino-lpc176x/archive/ma
 framework         = arduino
 board             = nxp_lpc1769
 build_flags       = -DTARGET_LPC1768 -DU8G_HAL_LINKS -IMarlin/src/HAL/HAL_LPC1768/include -IMarlin/src/HAL/HAL_LPC1768/u8g ${common.build_flags}
+# debug options for backtrace
+#  -funwind-tables
+#  -mpoke-function-name
 lib_ldf_mode      = off
 extra_scripts     = Marlin/src/HAL/HAL_LPC1768/upload_extra_script.py
 src_filter        = ${common.default_src_filter} +<src/HAL/HAL_LPC1768>