I have finished porting the firmware, and I am happy: I had no major modification to do on the prototype for everything to work :)
At a glance, what I added:
- Mono aftertouch (or "channel pressure").
- Automatic filter tuning.
- A bootloader, to allow easy and riskless firmware updates.
- A cleaner MIDI implementation with CC and NRPN.
By the way, I was able to implement the WaveMod called "crossover" in true polyphony, and even allow it on the 2 oscillators, a small demo:
This allows a 4 single cycle sound as "partials", here I modulate it with the oscillators envelope, we can also hear the aftertouch modulating the filter brightness.