I'm having trouble reading/writing to internal flash on an STM32H743XI. For a while I've been erasing/programming sectors of internal flash from a custom bootloader without issue but I somehow got the chip into a state now where 4 sectors can no longer be read from and instead trigger a hardfault. I think it has to do with ECC but I'm having trouble verifying that or clearing the error. The issue persists through power cycle. The HAL functions for erasing/programming flash still execute on these bad sectors and return HAL_OK but if I try to read data anywhere in these sectors the MCU hardfaults.
Anyone have an idea of what the issue is and how to resolve it?
Debugger is also unable to access this memory as shown below:
