stm32g070, some custom boards start, others do not

[nielsbraspenning]

Hi,

We have some problems with booting a mcu (stm32g070), we have custom hardware.

i can generate a mxcube project that works fine, every time a power the mcu on the custom hardware. this works on
all pieces which we have produced

We created a project (the purpose of the hardware) and this works fine on one example of the custom hardware

On a other piece, it seems the mcu is not starting executing code. i am not sure if it just won't start or is locked-up.

I think that something in the project is causing this, and i have bypassed basically all code. so only the init's are left and the blinking of a led

[TDK]

The most likely scenario if most boards work but some do not is there are manufacturing issues. Check resistance of PA6 to ground or VCC. Put it as input with pullup and verify it gets pulled up. Do the same with pulldown. Verify current draw from the device is as expected.

If you don't have source code, you can use STM32CubeProgrammer to run and see where the PC gets stuck, although without the program context this is harder to debug. It should at least convince you that the chip is trying to do something.

[Tesla DeLorean]

Yeah, this was an Interstellar reference, It's Impossible, It's Necessary, when you're out of easy options, people writing big checks want to know why the silicon's "Not Working" you get into the extra-ordinary methods, as you approach impossible, you have to get more imaginative and try harder.

[nielsbraspenning]

The pin is used a output, and should enable a other piece of circuitry.

could drawing too much current from this pin also result in this issue?

[TDK]

More likely that the "other piece of circuitry" is the problem since the chip works fine if you don't enable PA6. But it gives you an avenue of attack. If raising PA6 causes a rail to drop, and the chip to reset, that's certainly consistent with that's you're seeing. But verify. Don't guess. Debugging is a very objective task, leave philosophy out of it.