Can the STM32G030 nRST pin disabled, or be used as GPIO?

[TLaut.1]

Hi guys!

We are running a project using STM32G0 MCU-s. We used STM32G031 in the previous iteration, but, due to budget reasons, we now ended up with STM32G030-s, beleiving these are basically interchangeable for our purposes.

Due to some board error, we now need to disable the NRST pin (or, rather set it up to be a GPIO in this case). On the older G031 boards, we can perform this from code through the option bytes, but to our surprise, the G030 manual misses these bytes altogether.

Using the older STM ST-Link utility, we were able to program the bytes on a test device somehow, and set up proper functionality, but I have a bad feeling about this. We have quite a few production devices where the programming pins are not accessible anymore, and we can only disable NRST with a software update. If we brick them, there's no way of bringing them back.

So... is there any way to safely set up NRST as GPIO on G030s from software? Is it a supported feature at all?

Thanks for your help!

[gbm]

Disabling NRST doesn't spoil anything as log as you don't reconfigure SWD pins. If your firmware uses SWD pins for some other functionality - then you have a problem. Still, there is a way to unbrick the chip.