STM32H742AG Flash Erase Bank 2 issues

[kip18]

Hello,

I am trying to erase flash bank 2 and then re-write with an incoming application. This appears to work that when I read back some of this sector it's changed to 0xFFFFFFFF, however when I restart or connect with STLINK it reads out as 0x00000000.

I only get errors if I try to write too fast after erasing flash and on POR the flash is read back as 0x00000000

I have tried unlocking flash and relocking after with

HAL_FLASHEx_Unlock_Bank2();
// erase
HAL_FLASHEx_Lock_Bank2();

// and or 
HAL_FLASH_Unlock();
// erase here
HAL_FLASH_Lock();

voltage range is correct. 

FLASH_EraseInitTypeDef erase_init;
erase_init.TypeErase = FLASH_TYPEERASE_SECTORS;
erase_init.Sector = 0;
erase_init.NbSectors = 1;
erase_init.Banks = FLASH_BANK_2;
erase_init.VoltageRange = FLASH_VOLTAGE_RANGE_3;
HAL_FLASHEx_Erase(&erase_init, &sector_error);

 

any suggestions or help would be appreciated

[TDK]

> when I restart or connect with STLINK it reads out as 0x00000000

Can you show a screenshot of where/how you're reading this out? 0 may indicate an error during reading rather than the actual value being read. Perhaps an ECC error.

HAL_FLASHEx_Erase returns HAL_OK?

No bank swapping enabled? SWAP_BANK=0?

The code presented looks fine.