STM32H747I-DISCO ST-LINK error (DEV_TARGET_NOT_HALTED), Failed to Erase Internal Memory Sector 0

[HassaanSaleem-101]

Hello everyone, I hope you're doing well. I'm currently working on the STM32H747I-DISCO board, implementing SBSFU on it. I accidentally put a PCROP Protection, which does not allow me to erase the flash memory sector 0, which corresponds to 0x08000000 of the flash memory, and the settings that I'm seeing on the Cube Programmer for the PCROP are: PROT_AREA_START1: value: 0x6, address: 0x08000600, and for the PROT_AREA_END1: value: 0xff, address: 0x0800ffff. I tried to change the option bytes, but no success. Then I tried to connect the board through the STM32 Cube programmer via hardware reset mode, so that it could go into the hardware reset state upon connection, but that didn't do the job either, and this caused me another problem, the ST-LINK error (DEV_TARGET_NOT_HALTED). Now I don't know what to do about these two problems, or how I might be able to solve them. If anyone knows anything related to solving these kinds of problems, that would be a big help. 

Thank you for reading this post.  

[Imen.D]

Hello @HassaanSaleem-101 ,

Try restoring the option bytes following the steps in this article, then disconnect and reconnect again.

Check also the target voltage when connecting with STM32CubeProgrammer.

To resolve DEV_TARGET_NOT_HALTED error, ensure the ST-LINK firmware is up-to-date and try connecting the board in 'under reset' mode using STM32CubeProgrammer (ensure the board is powered correctly).