ZX81 Polyphonic Sequencer Part 3 - E&MM Feb 1982 (Peter Maydew)
Wow, it didn't take much code or hardware to get a polyphonic sequencer together for the Sinclair ZX81!! All you need is a digital to analogue converter chip (DAC0801), a little extra circuitry & a handful of machine code. This article is scanned from my copy of Electronics & Music Maker, Feb 1982. Article written by Peter Maydew.