Really basic oscilloscope

Just for fun - probably not a substitute for spending a thousand dollars on a real one. Zoom into waveforms, being read from the Meowbit pins.

Brief video showing it reading a 0-3.3V signal twiddling a potentiometer.

up/down buttons change the y-scale
left-right buttons change the x-scale
A/B buttons offset the wave up and down the screen

By default it’s in ‘simulation’ mode where you can look at a precalculated sine wave, if you don’t have a circuit to actually connect to the pins or you don’t want to.

Press Menu to begin reading voltage on pin 0 instead.
Tie GND to ground otherwise you’ll get floating voltage noise probably.

ENSURE the voltage is only in the 0-3.3V range. You will probably harm your device if you don’t.

8 Likes

The sampling is pretty poor btw. It completely suspends sampling the voltage while it renders, so it’s glitchy when cycles repeat. It was only a quick hack to show the kids what a ‘bouncy’ push button looks like, and to show voltage sweeping with the potentiometer. Might try and make it a bit smarter some time, sampling in a background thread, that kind of thing.

1 Like