stm32c011 in-application option byte programming

[AndreasS]

Good morning,

I'm trying to program the user option bytes of the STM32C011 using the HAL. The objective of the test is to toggle the BOR bit.

 

 

static HAL_StatusTypeDef testOptionBytes()
{
 FLASH_OBProgramInitTypeDef obInit = {0};
 FLASH_OBProgramInitTypeDef obProgram = {0};
 FLASH_OBProgramInitTypeDef obCmp = {0};
 HAL_StatusTypeDef status = HAL_OK;

 HAL_FLASHEx_OBGetConfig(&obInit);

 status = HAL_FLASH_Unlock();
 assert(status == HAL_OK);
 status = HAL_FLASH_OB_Unlock();
 assert(status == HAL_OK);

 obProgram.OptionType = OPTIONBYTE_USER;
 obProgram.USERType = OB_USER_BOR_EN;
 obProgram.USERConfig = (obInit.USERConfig & OB_USER_BOR_EN) ^ OB_USER_BOR_EN;
 status = HAL_FLASHEx_OBProgram(&obProgram);
 assert(status == HAL_OK);

 HAL_FLASH_OB_Lock();
 HAL_FLASH_Lock();

 HAL_FLASHEx_OBGetConfig(&obCmp);
 assert(obInit.USERConfig != obCmp.USERConfig);

 return status;
}

 

When I step through the HAL code everything looks fine, the FLASH->OPTR register is written with the correct value, but the final assert() always fails.

 

Have I overseen something here?

Thanks in advance, Andreas

[mƎALLEm]

You need to call HAL_FLASH_OB_Launch()  after HAL_FLASHEx_OBProgram()