A problem while using mcu STM32G031J6Mx

[zhn.]

Hello,

I use STM32G031J6Mx pin4 as a output. But when I set this pin low, the mcu will be reset.

Somebody know why?

[KnarfB]

Doesn't happen to me on a STM32G0316-DISCO board. Maybe NRST is active? See NRST_MODE in flash option register.

[zhn.]

Please try to set pin4 as PA0，PA1 or PA2's output. Not PF2's. And then set the pin low.Looking forward to your reply!

[KnarfB]

What is the value of your NRST_MODE in flash option register? You may use STM32CubeProgrammer to find that out. The factory default is 3, which enables NRST IO. Set the NRST_MODE to 2, does the chip still reset?

[zhn.]

Thx KnarfB,I have solved the problem according to your method.But I still have a question.Why I set this pin as PF2's output with the NRST_MODE=3, the chip will not reset?

[KnarfB]

Pls. see RM0444 Reference manual section 5.1.2

[zhn.]

Thank you,dude.