STM32 Virtual COM Port and BREAK

[T B]

Posted on January 29, 2018 at 12:02

Hello!

Is it possible to send a UART break (0.3 seconds) over the Virtual COM Port.

It seems that UART break is connected with NRST.

-Thomas

[Bogdan Golab]

Posted on January 29, 2018 at 15:57

Yes, I see the same on my nucleo boards. It seems that st-link reacts to this signal the way you described.

[Andrew Neil · Accepted solution]

Posted on January 29, 2018 at 16:08

So, if you want the BREAK to reach the target STM32, you'll have to use a separate connection direct to the target's UART pins (and break the links to the ST-Link UART if you want to use those pins)

[Bogdan Golab]

Posted on January 29, 2018 at 16:11

I guess we are taking about VCOM in this case (at least when talking about nucleo board). In case of F3discovery I do not know how it was possible to send break to the st-link as it does not emulate the VCP.

[T B]

Posted on January 30, 2018 at 14:02

http://www.st.com/en/evaluation-tools/stm32f3discovery.html

 

Virtual COM port with ST-LINK/V2-B only