So… after some cursing at me being dimwitted enough to get the amplifier around the wrong way… and luckily the amplifier is a tough little beast… I managed to get some basic functions going.
It is supposed to be polyphonic, the synthesizer supports it, and it does actually work, but it seems my GPIO arrangement isn’t picking up multiple buttons correctly.
Ahh well, we’ll get there. 🙂 At least it is making noises and flashing lights on cue, so in that sense, a minimum viable product has been achieved.
Ohh, and I was able to bump the sample rate to 16kHz. 32kHz was a bit much for the little MCU though, it couldn’t quite keep up.
Code size at this point is 3.6kB… so still lots of room left. The answer might be to implement an I²C slave mode so I can interrogate it from the host.