Nice project!
> Due to debouncing troubles, it seems to be double-reading each pulse. At some point I should throw a scope on it to confirm what the problem is, but it works quite adequately as-is. (My first try only had a 10ms delay, which empirically resulted in septuple-reading each pulse…)
Needless to say, this is not the canonical way to count pulses. A more typical and accurate loop would look like
if digitalRead(pin):
count +=1 # register the pulse
sleep(0.01) # debouncing delay
while digitalRead(pin): # wait for end of pulse
pass
sleep(0.01) # debouncing delay