G431 will run (somewhat) with debugger, but not on its own.

[Tobe]

I have made a prototype, and it runs as just after upload. But when i just turn on the power, it wont. It does not matter if the st-linkv3 ist connected or not. When i reset it, via the NRST pin, it also wont run.

I already used the HSE and HSI, and checked on a nucleo, that my code is working (it does).

I dont know how i further can investigate this. The level of NRST is clean and the level is good.

[SofLit]

Hello,

What about Boot pin? connected to VDD or GND?

See for example this thread: https://community.st.com/t5/stm32-mcus-products/stm32h723zgt6-will-not-reboot-after-powering-off/m-p/650457

[Tesla DeLorean]

BOOTx pins or settings?

Get a USART working very early in the Reset Handler so you can express signs-of-life. Could perhaps use GPIO/LEDs at as simpler level. Have Hard Fault and Error Handlers output actionable data.

[Tobe]

Neither: It is connected to RX of a CAN chip. See attached the waveforms.

pink is Boot0 pin, blue is 3.3V of STM

[SofLit]

Hello,

Neither: It is connected to RX of a CAN chip. See attached the waveforms.

Sorry.. I didn't catch that point!  How did you connect Boot pin? which CAN chip? could you please share schematics?

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pink is Boot0 pin, blue is 3.3V of STM

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Pink signal is rising. It should be connected to the ground. Why BOOT pin voltage is changing?

[Tobe · Accepted solution]

It works:

I had to set nSWBOOT0 to 0. See picture attached.

Thanks a lot.