I will post specific code and technical details if the solution isn't something trivial and requires more digging.
TLDR: Using python in jupyter notebook to send 'hello world' 10 times through the /dev/serial0 port of my raspberry Pi model 4 B to my arduino uno. Arduino uno receives this message then prints "hello world" to be picked up on the arduino serial monitor back on the Raspberry Pi
except after ~60 seconds, the serial monitor says "Login Incorrect" then starts spewing some technical data followed by what looks like the screaming with the horror of a thousand tortured souls used to summon an eldritch horror beyond human comprehension. At this point my hello world starts saying "SerialException: write failed: [Errno 5] Input/output error" and I am no longer able to send hello world to the arduino.
Issue is fixed temporarily with a reboot, but after another minute it behaves the same.
My theory is that at some point in my workflow some wires are getting literally or figuratively crossed and at some point my Pi starts sending data from some other stream. Any idea what could be happening here?
Will have a link to the same post on the raspberry pi forums once that post gets approved.
