OTA update - sodaq board (arduino M0 compatible)

Question

I am trying to perform a firmware update from an SD card, on a Sodaq Sara AFF board. If i use the SDU.h library in my sketch, it fails the board check. See this link please.

I have edited the SDU.cpp myself to force the selection of ARDUINO_SAM_ZERO. It is now :

__attribute__ ((section(".sketch_boot")))
unsigned char sduBoot[0x6000] = {
  #include "boot/mzero.h"
};

I have increased the size to 6000 otherwise it was complaining too many initializers.

I also have changed the SD_SS_PIN to match my pin on the SDUboot.ino, under extras. Afterwards, i recompiled it with build.sh in the same folder.

But I am unable to perform the firmware update. After power cycling the board (original code: the blink example, target update: blink with a faster rate) - the original firmware remains.

I exported the firmware using arduino IDE -> export compiled bynary, and tested both versions with and without bootloader.

Any help would be appreciated.

Answer 1

SOLVED!

I have compiled my own SDUBoot.ino with fixed SDU_START 0x2000 and for SODAQ Sara (boot/sodaq_sara.h). My sketch with #include "SDU.h" compiles successfully. The board package is also installed in Arduino (http://downloads.sodaq.net/package_sodaq_samd_index.json). Here my code with changes (base is SodaqCore-samd-1.8.6-sodaq from Github):

File libraries/SDU/extras/SDUBoot/SDUBoot.ino:

#include <SD.h>
#include <FlashStorage.h>

#define SDU_START    0x2000
#define SDU_SIZE     0x4000

#define SKETCH_START (uint32_t*)(SDU_START + SDU_SIZE)

#ifndef SDCARD_SS_PIN
#define SDCARD_SS_PIN 10
#endif

#define UPDATE_FILE "UPDATE.BIN"

FlashClass flash;

// Initialize C library
extern "C" void __libc_init_array(void);

int main() {
  init();

  __libc_init_array();

  delay(1);

  if (SD.begin(SDCARD_SS_PIN) && SD.exists(UPDATE_FILE)) {
    File updateFile = SD.open(UPDATE_FILE);
    uint32_t updateSize = updateFile.size();
    bool updateFlashed = false;

    if (updateSize > SDU_SIZE) {
      // skip the SDU section
      updateFile.seek(SDU_SIZE);
      updateSize -= SDU_SIZE;

      uint32_t flashAddress = (uint32_t)SKETCH_START;

      // erase the pages
      flash.erase((void*)flashAddress, updateSize);

      uint8_t buffer[512];

      // write the pages
      for (uint32_t i = 0; i < updateSize; i += sizeof(buffer)) {
        updateFile.read(buffer, sizeof(buffer));

        flash.write((void*)flashAddress, buffer, sizeof(buffer));

        flashAddress += sizeof(buffer);
      }

      updateFlashed = true;
    }

    updateFile.close();

    if (updateFlashed) {
      SD.remove(UPDATE_FILE);
    }
  }

  // jump to the sketch
  __set_MSP(*SKETCH_START);

  //Reset vector table address
  SCB->VTOR = ((uint32_t)(SKETCH_START) & SCB_VTOR_TBLOFF_Msk);

  // address of Reset_Handler is written by the linker at the beginning of the .text section (see linker script)
  uint32_t resetHandlerAddress = (uint32_t) * (SKETCH_START + 1);
  // jump to reset handler
  asm("bx %0"::"r"(resetHandlerAddress));
}

File libraries/SDU/extras/SDUBoot/build.sh:

#!/bin/sh -x

ARDUINO=arduino
SKETCH_NAME="SDUBoot.ino"
SKETCH="$PWD/$SKETCH_NAME"
BUILD_PATH="$PWD/build"
OUTPUT_PATH="../../src/boot"

if [[ "$OSTYPE" == "darwin"* ]]; then
    ARDUINO="/Applications/Arduino.app/Contents/MacOS/Arduino"
fi

buildSDUBootSketch() {
    BOARD=$1
    DESTINATION=$2

    $ARDUINO --verify --board $BOARD --preserve-temp-files --pref build.path="$BUILD_PATH" $SKETCH
    cat "$BUILD_PATH/$SKETCH_NAME.bin" | xxd -i > $DESTINATION
    rm -rf "$BUILD_PATH"
}

mkdir -p "$OUTPUT_PATH"

buildSDUBootSketch "SODAQ:samd:sodaq_sara" "$OUTPUT_PATH/sodaq_sara.h"

File libraries/SDU/src/SDU.cpp:

#include <Arduino.h>

#include "SDU.h"

__attribute__ ((section(".sketch_boot")))
unsigned char sduBoot[0x4000] = {
  #include "boot/sodaq_sara.h"
};

Sketch file sdu_test.ino:

#include <Arduino.h>
#include "SDU.h"

#if defined(ARDUINO_SODAQ_SARA)
#define DEBUG_STREAM SerialUSB
#else
#error "Please select the SODAQ SARA as your board"
#endif

#define DEBUG_STREAM_BAUD 115200

String message;

void setup() {
  // Start communication.
  DEBUG_STREAM.begin(DEBUG_STREAM_BAUD);

  while (!DEBUG_STREAM) {
    // Wait for Serial Monitor to be opened.
  }

  message += "Sketch compile date and time: ";
  message += __DATE__;
  message += " ";
  message += __TIME__;

  // print out the sketch compile date and time on the serial port
  DEBUG_STREAM.println(message);
}

void loop() {
  // add you own code here
}

File arduino/50/.arduino15/packages/SODAQ/hardware/samd/1.8.6/variants/sodaq_sara/linker_scripts/gcc/flash_with_bootloader.ld add these lines:

KEEP(*(.sketch_boot))

. = ALIGN(0x2000);

here:

...
SECTIONS
{
    PROVIDE(__sodaq_firmware_state = ORIGIN(FLASH) - 0x100);

    .text :
    {
        __text_start__ = .;

        KEEP(*(.sketch_boot))

        . = ALIGN(0x2000);
        KEEP(*(.isr_vector))
        ...

On SD card (formatted as FAT32) I have stored the renamed file UPDATE.bin without bootloader of the compiled sketch file. Pin D10 is connected and used as chip select CS.

Build boot hex files:

$ cd libraries/SDU/extras/SDUBoot
$ ./build.sh

Version 1.8.6-sodaq has these missing lines on arduino_zero variant but not on sodaq_sara variant.