How to use serial wire debug pins after programming the stm32

[Tommino]

Hi,

I am using the serial wire debug SWDIO and SWCLK on PA13 and PA14 to program an stm32g031. Can I use these pin after the debug? If yes, do I have to modify some dedicated register (in addition to the GPIO registers) to use thiese pins as GPIO?

[waclawek.jan]

> Can I use these pin after the debug?

Yes.

> do I have to modify some dedicated register (in addition to the GPIO registers) to use thiese pins as GPIO?

In 'G0, AFAIK, no.

Note, that if you also use the NRST pin as GPIO, the chip can't be programmed anymore.

JW

[Tesla DeLorean]

I think the trick with the G0/NRST would be to have a) some dwell time between start-up and reconfiguring the pins, or b) some use case controlled method of resetting or deconfiguring pins, say via a command on serial port.

Perhaps use a button inputs?

[Tommino]

Hi @Community member​ and @Community member​ 

I am not interested in using the NRST pin as GPIO but only the PA13 and PA14 as GPIO

So your opinions are that I should simply code them as GPIO without any other cautions? Neither on the debug side?

What I found in the manual does not help me a lot. Can you take a look at this?

[waclawek.jan]

I don't have first-hand experience with 'G0 in particular, but this is what I did/do in other small-pin-count models, .eg. 'F0 and 'L0.

JW