I have a working program on my own board using a STM32G081KBU6. Debug using SWD and programming a release version works fine. As long as RDP remains at Level 0, I'm able to debug, erase and reprogram updates to the board.
Usually for other ST MCU's that I've used, once I've finalized a release version, I usually do the bare minimum of changing RDP to Level 1 to prevent code readout. If I need to do a firmware update, I'll just regress RDP back to Level 0 and update to the new version.
However, for this device, once I change the RDP to level 1, it seems like the SWD debug port is completely killed, and Cube programmer is unable to connect to the device anymore.
I've tried all the connection and reset modes in Cube programmer, including powering the board on and trying to connect immediately. I'll only keep getting this error.
I'm sure that I did not accidentally set RDP to Level 2, as the setting was done in Cube Programmer itself, and I've verified this on more than one board. Note also that the board is not bricked - it still runs the last programmed firmware as normal. I just can't regress the RDP to reprogram updates.
Does anyone have any idea on what is causing this?
