Ah, the joys of trying to come up with creative ways to get feedback from your code when literally nothing is available. Can I make the beeper beep in morse code? Can I just put a variable delay in the code and time it with a stopwatch to know which value was returned from that function? Ughh.
Some of us have worked on embedded systems or board bringup. Scope and logic analyzer ... Serial port a luxury.
IIRC Windows has good support for debugging device drivers via the serial port. Overall the tooling for dealing with device drivers in windows is not bad including some special purpose static analysis tool and some pretty good testing.
Yeah. Been there, done that. Write to an unused address decode to trigger the logic analyzer when I got to a specific point in the code, so I could scroll back through the address bus and figure out what the program counter had done for me to get to that piece of code.
