STM32F469I-DISCO virtual com port USART3?

[PGroe.2]

Hi there,

My new STM32F469I-DISCO just arrived I stumbled upon this part in user manual (UM1932):

4.11 Virtual COM port

The serial interface USART3 is directly available as a virtual COM port of the PC connected

to the ST-LINK/V2-1 USB connector CN1. The virtual COM port settings are configured as:

115200 b/s, 8 bits data, no parity, 1 stop bit, no flow control.

So I did a quick test in CubeIDE and enabled USART6 with default settings and just send one char to my USB-Serial Adapter to check on my PC if the char arrives... and it does.

Now I tried the same with USART3. As I plug in the DISCO board via its integrated STLink my Linux system tells me that a new serial device "ttyACM0: USB ACM" . So again I opened a serial terminal on ttyACM0 but no char gets received from the board.

What I am doing wrong? Or is my understanding wrong? Is "USART3" meant to be part of the STM32F103xxx STLInk or is it part of the boards STM32F469xxx?

[PGroe.2 · Accepted solution]

Found a solution to myself:

When I enabled USART3 it enabled the default pins PD8 / PD9 but the lines that go from the STM32F469 to the STLink STM32F103 are PB10 / PB11 which are the alternate pins for USART3. So I enabled PB10 / PB11 as USART3 manually and violá, the char arrives at serial device ttyACM0.