Custom Board: BARTH STG-850 serial port not working

Hi erveyone,

I try to use a BARTH STG-850 mini PLC with Platformio.

The PLC is based on a STM32F091CC MCU.

Fortunately someone else made a custom board for this: GitHub - saierd/platformio-barth-stg: Example for using Barth STG-820 and STG-850 boards with PlatformIO

So far everything works as expected, except for the serial port.

If I clone that repo and edit the main.cpp ike this:

#include <Arduino.h>

void setup()
{
    Serial.begin(9600);
}

void loop()
{
    Serial.println("A");
    delay(1000);
}

and set monitor_encoding to hexlify in the platformio.ini

I get 26 FE as output in pio device monitor every second.

The is a integration into the ARDUINO IDE from BARTH from 2017 on which the platformio integration is based (linked in the README).
If I use that with the Arduino IDE, the serial port works as expected (but the outputs 5 to 8 do not work :face_with_diagonal_mouth:)

So I assume its just a minor issue in this platformio integration that makes the Serial port misbehave.

If anyone can point out to me what needs to be done in order to get this working,I would be really happy :slightly_smiling_face: