After some obligatory fumbling around
Poke the button and get appropriate music
It had to be a timing problem with otherwise correct code
Given that you can’t see the result, why send the commands?
It runs pretty much all day, every day
There’s no display: you have no idea what’s going on.
An in-depth talk about my adventures restoring that old HP 7475A plotter for the Poughkeepsie ACM Chapter…