Problems creating Virtual COM port on STWINKT1 (STM32L4 MCU)

[SFalc]

Hello,

I'm writing a basic program that prints something over and over through VCOM port on USB-OTG, on a STWINKT1 board.

This board uses a STM32L4R9ZIJ6 MCU, so I followed this guide: https://www.youtube.com/watch?v=rLnQ3W8gmjY (and many others).

The problem is that the PC doesn't see the board at all.

The board doesn't show up as COM nor as "unrecognised device".

I can't understand what I'm doing wrong, how can I make it to work?

Thanks and have a nice day,

SF

[Imen.D]

Hello @SFalc​ ,

Let me first welcome you to the Community :)

I advise you to follow this FAQ: USB device not recognized,

Also an idea to try a different cable and PC, check if the board work correctly.

When your question is answered, please close this topic by choosing Select as Best.

Imen

[SFalc · Accepted solution]

Hello @Imen DAHMEN​ 

Thank you!

In the end I found the problem: STM32CubeIDE enables and initializes by default the MicroSD interface, and if there's no MicroSD card in the slot, the program get stuck in the Error Handler infinite loop.

Disabling the MicroSD or inserting a card in the slot fixes the problem.

Thanks and have a nice day,

SF

[Imen.D]

Hi @SFalc​ ,

Glad to know the issue has been solved :).

Please allow me to close this thread and thank you for your contribution.

Imen