A simplified version of 1-bit synthesis that runs on the Arduino. We'll use the standard Arduino IDE instead of assembly - the Arduino should be more than powerful enough to do 1-bit synthesis at 22.05kHz without any crazy optimizations. Bonus points if we can get 44.1kHz, although the idea of super high frequency 1-bit waves is not too enticing…
Ideally we'd build some kind of library for 1-bit synthesis (maybe rendering MIDI), one (or more) demo compositions, and a blog post explaining how it was done.
1-bit velocity: We can't adjust amplitude, since we're dealing with only 1 bit of information. What we can do is adjust pulse width. Higher velocity notes will get larger pulse widths, and vice versa.
1-bit polyphony: We can't add notes together. What we can do is OR or XOR (or AND) concurrent samples. Tristan said he started out with XOR but used OR in his latest work. If we build a library we probably want a way to specify the “blending mode”.