MEMORY
{
  FLASH (rx)      : ORIGIN = 0x08000000, LENGTH = 1024K
  RAM (xrw)       : ORIGIN = 0x20000000, LENGTH = 128K
  MEMORY_B1 (rx)  : ORIGIN = 0x60000000, LENGTH = 0K
  CCMRAM (rw)     : ORIGIN = 0x10000000, LENGTH = 64K
}

MEMORY
{
  FLASH (rx)      : ORIGIN = 0x08001000, LENGTH = 1024K
  RAM (xrw)       : ORIGIN = 0x20000000, LENGTH = 128K
  MEMORY_B1 (rx)  : ORIGIN = 0x60000000, LENGTH = 0K
  CCMRAM (rw)     : ORIGIN = 0x10000000, LENGTH = 64K
}

#define VECT_TAB_OFFSET  0x0

#define VECT_TAB_OFFSET  0x1000

# Reconfigure vector table offset register to match the application location
set *0xe000ed08 = 0x1000

# Get the application stack pointer (First entry in the application vector table)
set $sp = *(unsigned int*)0x1000

# Get the application entry point (Second entry in the application vector table)
set $pc = *(unsigned int*)0x1004

# Set flash parallelism mode to 32, 16, or 8 bit when using STM32 F2/F4 microcontrollers
# Uncomment next line, 2=32 bit, 1=16 bit and 0=8 bit parallelism mode
#monitor flash set_parallelism_mode 2

# Set character encoding
set host-charset CP1252
set target-charset CP1252

# Reset to known state
monitor reset

# Load the program executable
load        

# Reconfigure vector table offset register to match the application location
set *0xe000ed08 = 0x1000

# Get the application stack pointer (First entry in the application vector table)
set $sp = *(unsigned int*)0x1000

# Get the application entry point (Second entry in the application vector table)
set $pc = *(unsigned int*)0x1004

# Reset the chip to get to a known state. Remove "monitor reset" command
#  if the code is not located at default address and does not run by reset.
#monitor reset

# Enable Debug connection in low power modes (DBGMCU->CR)
set *0xE0042004 = (*0xE0042004) | 0x7

# Set a breakpoint at main().
tbreak main

# Run to the breakpoint.
continue

    .text :
    {
        _image_start = .;
        KEEP(*(.isr_vector))

        LONG((_image_end - _image_start) / 4);    /* application size, in 4-byte words */
.............
/* после всех text, romem и data: */
    .text.crc :
    {
        . = . + 4;  /* reserve space for CRC */
        _image_end = .;
    } > TEXT

     _image_start = .;
.....
     _image_end = .;

void USB_LP_CAN1_RX0_IRQHandler(void)
{
    if((CAN1->RF0R & CAN_RF0R_FMP0)!=0) /* check if a message is filtered and received by FIFO 0 */
    {
        CAN_ReceiveData = CAN1->sFIFOMailBox[0].RDLR;   /* read data */
        CAN_CmdType = CAN1->sFIFOMailBox[0].RDHR;
        CAN_Identifier = CAN1->sFIFOMailBox[0].RIR;
        CAN1->RF0R |= CAN_RF0R_RFOM0;                  /* release FIFO */
        data_ready = 1;
    }
    else {
          //error_flag |= CAN_ERR;
          CAN1->TSR |= CAN_TSR_ABRQ0;
          CAN1->IER &= ~CAN_IER_ERRIE;
    }
}

int boot_main(void)
{

    __disable_irq();

    GPIO_Config();
    CAN_Config();
    Start_TIM2();

    __enable_irq();

    //load parameters from flash
    memcpy(&flashParams, (uint32_t*)FLASH_PAGE127, sizeof(flashParams));
    
    // notify other party that we are alive
    CAN_Send(UNIT_ID , READY, 0);
  
  /* Infinite loop */
  while (1)
  {
      //get data from CAN
      if (data_ready)
      {
          data_ready = 0;
          WriteAppToFlash();
      }

      //timeout to exit to main application
      if (sec_count > TIMEOUT)
      {
          sec_count = 0;
          if (flashParams.state == LAST_BOOT_OK)
          {
              JumpToApp();
          }
          else  //try to program flash from the buffer
          {
                   
          }      
      }

  }
}

void WriteAppToFlash(void)
{
    /* Porgram APP to FLASH -------------------------------------------------------------*/

    // Unlock the Flash
    FLASH_Unlock();

    /* Clear All pending flags */
    FLASH_ClearFlag(FLASH_FLAG_EOP | FLASH_FLAG_PGERR | FLASH_FLAG_WRPERR | FLASH_FLAG_BSY);

    uint32_t done = 0;
    uint32_t page;
    uint32_t page_addr;
    uint32_t page_addr_end;

    /* Erase the FLASH pages */
    for(page = 0; page < 20; page++)  //main program takes 20 pages
    {
        page_addr = (page * FLASH_PAGE_SIZE) + APPLICATION_ADDRESS;
        FLASHStatus = FLASH_ErasePage(page_addr);
        if (FLASHStatus != FLASH_COMPLETE)
            break;
    }

    /* Program Flash */
    page = 0;
    while (page < 20 || !done)
    {
        Address = (page * FLASH_PAGE_SIZE) + APPLICATION_ADDRESS;
        page_addr_end = Address + FLASH_PAGE_SIZE;
        while((Address < page_addr_end))
        {
            // Get packet from CAN
            //?????????

            //Program packet to flash
            FLASHStatus = FLASH_ProgramWord(Address, Data);
            Address = Address + 4;
            addr_data = addr_data +4;
            if (FLASHStatus != FLASH_COMPLETE)
            {
                //done = 1;
                break;
            }
        }
        page++;
    }

    FLASH_Lock();

    /* Jump to User define Application Address */
    JumpToApp();
}