TL;DR I got the debug output from Signet's UART
- The reference manual is well organized!
- I added lots of comments to the code to reference which section of which document that it came from
- I got confused with calculating the UART BR register value for a desired baud rate, but that doesn't really matter because...
- The UART port "just worked" with `screen` on Fedora 38. I'm not sure if I transposed something in the command on my Debian 12 box or if they have different defaults for parity/stop bit, or something else is going on. I'm busy the next few days, but I'll boot that box again to investigate further in a few days
- The reason my previous test was constantly writing to the `screen` was because the debug output is continuous as there are apparently some debug print in the main loop
Overall, this is excellent news. Not only did I get the ability to see runtime debug print statements from the firmware, but I also got familiar with how to find low level information about this MCU.
Plus with the notes I made in the code, next time I'm going through it (or someone else is), it'll be easier to trarck these things down.