USBSerial on STM32F412ZG (NUCLEO-144)

[faydrus (Dan Fay)]

I am using Mbed OS 6.6 with an STM32F412ZG. When I make a simple project with USBSerial, it builds without issue.

However, when I plug in a USB cable to the “User USB” connector on the opposite side of the board from the built-in ST-Link, the USB does not successfully enumerate.

Is there something special that I need to do to get the USB device to work correctly with the NUCLEO-144 boards? I’m having a similar issue with a NUCLEO-743ZI2-based NUCLEO-144 board and Mbed OS 5.15.

Any help or suggestions would be greatly appreciated.

Thanks!

-Dan Fay

[JohnnyK (Jan Kamidra)]

Hello,

I only know, the DTR signal is required from your serial application on your PC, if the USB was recognized by the PC.

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With the H743 there were an issue

Mbed NUCLEO_H7743ZI2 doesn't support USBDEVICE

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BR, Jan