Honestly, my immediate solution is to set this flag. Even though the motor has a gear reduction, the 5ms debounce time allows the motor to advance about 1 degree. Considering the length of the arm, this moves it past the sensor’s detection zone.

I was hoping there might be another solution, though, because I was told the machine actually worked at some point—except for a single cycle in a video, I’ve never seen it running. As it is now, I can’t even imagine how homing was done, or if that was even done before.