Re: Soft serial 9k6 for debugging on free GPIO?
This Zephyr example does UART over GPIO:
Here's a picture with the system overview:
However it receives the data to send via RPMsg from a second core running Linux and vice versa.
It could be possible to remove the RPMsg related part and rewrite the code into a driver and select that peripheral as a debug console in board's DTS file.
The code requires a hardware timer and supports just 8N1 format.