Add UART port

[brucebotes]

HI Lonehog.
Thank you for this great JTAG version that just works with Openocd without hassles. I searched the internet for days trying to find something similar - which was openocd friendly - without real success. There is the dirtyJtag project with and another patched Openocd version which I could not get to work.

The Pico board solution is way cheaper option and something I find fascinating. Thanks.

Your project made me aware that the CMSIS-DAP project has an ability to compile both the JTAG and SWD modes, and maybe even to co-exist? I am not sure how to implement it at all...

I would like to use an additional UART port with the JTAG option - similar to that of the Raspberry Pico Debug probe. I compared the two source repositories hoping to find an easy solution, but unfortunately realized that there are many "other' things to be aware of - especially the freeRTOS designs, Tiny USB and cmake build setups.

Can you please give me pointers as to how you would approach something like this?

• I noticed that you deliberately excluded the cdc_task() in main(), which I assume would be required for the UART/USB bridge)?
• The JTAG pins were configured in a specific way, I assume that was to by-pass the PIO functions - which I is a next level of complexity for me...
• Would the UART bridge require PIO and the cdc_task() to work?
• Would the addition of the UART impact on the stability of the JTAG solution. Is it possible...
• Could the solution be as simple as enabling the JTAG define in the DebugProbe source and just build it? Where are the pin definitions...

Thank you in advance.