ESP32-POE getting garbage input

[anicolao]

I have built and installed micropython firmware on two similar Olimex boards, a GATEWAY device and an ESP32-POE device.

Things are mostly working, but on the POE device I often see garbage provided as input to the micropython REPL. I don't have a clear understanding of why this might be/where the garbage characters are coming from—it's as though something is connected to serial and providing input into the console, but all I have connected is the ethernet cable for network and power, and I am accessing the REPL via the websocket interface.

I would attempt to ignore it, but occasionally the garbage input includes a control-C which interrupts the micropython code I am running and is a showstopper.

Ideas on how to debug/understand what's happening would be very helpful. Note that the GATEWAY device which is in most respects the same does not exhibit the problem; only the PoE device does.

[LubOlimex]

Is it only during boot or also user software that is throwing garbage?

It is probably wrong baud rate or terminal settings, try with 115200. Try with another serial terminal software.

It can be also wrong settings of the environment or bad USB cable/port.

[LubOlimex]

Which pins exactly do you use for the serial output in the GATEWAY and in the POE? Maybe there is some specific multiplexing in the PoE that causes it. Maybe some other hardware is attached to that serial line?