aka Sinclair ZX81. There was such a program in Your Computer that would toggle between fast and slow mode to generate tones. It was a actually a trivial 8 or 16

aka Sinclair ZX81. There was such a program in Your Computer that would toggle between fast and slow mode to generate tones. It was a actually a trivial 8 or 16 step tracker, so you could even make beats... And here's the program listing! https://archive.org/details/your-computer-magazine-1982-03/page/n33/mode/2up https://archive.org/details/your-computer-magazine-1982-03/p...