STM32L552RET, USB connection only throuth Error 43

[TFalk.1]

I am working on a schole projekt and there I neded to design a PCB that can talk to the PC over USB. whiel doing that I am not able to figure aout whie the USB connection dous not work if it is not set for programming.

In detail:

The USB Connection is ISOLATED with a ADUM3160.

When I set BOOT0 to HIGH for programming over USB, everything works fine.

When I set it to LOW for using it as a Virtual Com Port it dous not work, I triued other Middle ware states suche as HID but the same error code 43.

I trued enabeling the Pullup from the Isolater only five secondes after everything was initilysed but that did not work.

[Imen.D]

Hello @TFalk.1​ and welcome to the Community :)

Have a look to this FAQ: USB device not recognized, it may help you.

Check the jumpers removed, and I advise you to validate your USB CDC configuration with a basic USB CDC device application in the STM32 USB training.

Best Regards,

Imen