Problems when reading from FLASH; STM32F4

[Jake2451]

I successfully write to FLASH but when I try to read I get 0.

First I read some data from keyboard to initialize "inter" variable.

Then I store it in FLASH, but I can't read it.

Here is what I've added to linker .ld file:

/* Specify the memory areas */
MEMORY
{
RAM (xrw)      : ORIGIN = 0x20000000, LENGTH = 128K
FLASH (rx)      : ORIGIN = 0x8000000, LENGTH = 384K
DATA (rw)	: ORIGIN = 0x8060000, LENGTH = 128K
}
 
.user_data :
  {
    . = ALIGN(4);
     KEEP(*(.user_data))
    . = ALIGN(4);
  } > DATA
  .preinit_array     :
  {

Obviously I've inserted this in main.c:

__attribute__((__section__(".user_data"))) const uint32_t userConfig[32];

This is how I'm dealing with writing to FLASH:

/* Writing to memory */
 
 HAL_FLASH_Unlock();
    __HAL_FLASH_CLEAR_FLAG(FLASH_FLAG_EOP | FLASH_FLAG_OPERR | FLASH_FLAG_WRPERR | FLASH_FLAG_PGAERR | FLASH_FLAG_PGSERR );
    FLASH_EraseInitTypeDef EraseInitStruct;
    EraseInitStruct.TypeErase = FLASH_TYPEERASE_SECTORS;
    EraseInitStruct.VoltageRange = FLASH_VOLTAGE_RANGE_3;
    EraseInitStruct.Sector = FLASH_SECTOR_7; //Specify sector number
    EraseInitStruct.NbSectors = 1;
    uint32_t SectorError = 0;
    if(HAL_FLASHEx_Erase(&EraseInitStruct, &SectorError) != HAL_OK) {
        //Erase error!
    }
    HAL_FLASH_Program(TYPEPROGRAM_WORD,userConfig,inter->moder);
    HAL_FLASH_Program(TYPEPROGRAM_WORD,userConfig+1,inter->prc);
    HAL_FLASH_Program(TYPEPROGRAM_WORD,userConfig+2,inter->cpr);
    HAL_FLASH_Program(TYPEPROGRAM_WORD,userConfig+3,inter->pos_mul_factor);
    HAL_FLASH_Program(TYPEPROGRAM_WORD,userConfig+4,inter->speed_mul_factor);
    HAL_FLASH_Program(TYPEPROGRAM_WORD,userConfig+5,inter->PWM_prc);
    HAL_FLASH_Lock();

and that is how I try to read:

/*function that reads stored data*/
void ReadConfiguration(Interface * inter)
{
 
 
	inter->moder=userConfig[0];
	inter->prc=userConfig[1];
	inter->cpr=userConfig[2];
	inter->pos_mul_factor= userConfig[3];
	inter->speed_mul_factor=userConfig[4];
	inter->PWM_prc=userConfig[5];
}

But it returns 0 on each field of "inter" variable.

Data are stored in FLASH and I can check it in STM32 ST-LINK Utility:

Hera are some screens from debug perspective:

This is after reading from keyboard and writing to FLASH:

Data in userConfig[] are correct but it writes 0 to "inter" variable

And here are FLASH registers:

The core is clocked by 100MHz so the latency is set correctly.

There is no read protection.

I have no idea so I'm asking for help.

[Tesla DeLorean · Accepted solution]

Compiler looks to be folding.

Check the address reported in .MAP file

Make this volatile not const

[Jake2451]

Thanks a lot! I've made this volatile and it works.

The mistake comes from here: https://stackoverflow.com/a/28505272

[Tesla DeLorean]

Thankfully my understanding of this predates the internet..