I try to change the option bytes of a STM32G070R from my program. i think I did everything a written in the doc:
- clear FLASH_CR_LOCK with the FLASH->KEYR sequence and wait till it is clear
- clear FLASH_CR_OPTLOCK with the FLASH->OPTKEYR sequence and wait till it is clear
- set FLASH->OPTR to the new value
- wait till all busy bits in FLASH->CR are clear
- set FLASH->CR = FLASH_CR_OPTSTRT (or only set bit FLASH_CR_OPTSTRT)
- wait till BSY1 in FLASH->CR is clear
- set FLASH_CR_LOCK and FLASH_CR_OPTLOCK
- reset the device and check FLASH->OPTR
but it is unchanged
I think the problem is right after setting FLASH->OPTR, reading it back then also returns the old value.
I wanted to check HAL functions but I can't find any FLASH_EX for it. I have G0 series package 1.3.0 which seems to be the latest.
It works with Cube programmer via SWD and UART = bootloader.
Which is the command via UART to bootloader to change option bytes? I can't find it in AN3155.
Thanks for any help.
