Getting a strange signal on USART1 pin PA9 (STM32F407 Discovery board). I'm using MXCube and Atollic True Studio.

[Dan in WY]

[waclawek.jan]

If a pin on a Disco/Nucleo/Eval does not work as you expect, check the manual/schematics where is that pin connected.

In this particular case, disconnect C49.

JW

[Dan in WY · Accepted solution]

I just enabled the 2nd com port and it works fine. I don't think I have the tools to unsolder C49.