Another potted music chip! Figuring them out is half the fun;-)
The PX088A is a simple, nondescript single-tune chip. Found out it plays the main theme from Beethoven’s Für Elise. The recommended configuration turned out to be a battery killer, but I was able to get it working with a few adjustments.
As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub
