Nucleo-G031K8 Program Will Not Start With 12v on VIN Pin LD1 Flashing Slowly

[LAURENCE]

Hi there,

I have a Nucleo-G031K8 evaluation board and am unable to get the program to start when connected to an external power supply. I have a bench top power supply connected to the VIN pin with 12v+ The LD2 led is light indicating power is working but the program fails to initialize and LD1 slowly flashes. The program works as expected when connected to my pc via USB but the program won’t start when using the external supply. The board is in it’s default configuration with respect to jumpers and solder bridges and I opened a brand new unit and attempted to power it via the VIN pin before connecting it to my PCB to verify that no circuit issues or damage is causing this. Please advise.

Thanks

[LAURENCE]

 

I really appreciate the help. Is it safe to assume these user configuration settings are how I control the NRST behavior? I'm not sure what I'm looking for exactly. Like I said I'm new to the STM32 family so bear with me...

Thanks,

[TDK]

Any debugger will work, the onboard one would be a lot simpler.

Looks like your NRST pin is in GPIO mode, so the level on there shouldn't affect the program.

You didn't answer the question about the 3.3V rail.

[LAURENCE]

Ok for some reason it is working now. I am not sure exactly why I had already updated the firmware stm32cubeide alerted me of the out of date firmware and offered up the latest version. that said I downloaded the firmware updater via the link you provided and even though the firmware version appeared to be the exact same I updated it again it started working! not sure why that is but I'll take it! Thanks guys!

IF anyone can offer some insight into what mighty have happened there I'm all ears! Also the led is still flashing but the program is working fine. not sure wtf happened there.....

[LAURENCE]

Sorry, the answer is yes, 3.3v rail is stable.

[Tesla DeLorean]

Well I looked over the schematic, and didn't look like the link to the NRST could be disconnected, so the ST-LINK FW is the one blinking the LD1 and clamping the G031's NRST to ground.

ST goes back and forth on how this works