The KIM-1 was the first 6502-based computer, with 1K (actually 1152 bytes) of RAM and a 1MHz clock speed. It has serial routines, but the DECtalk Express it's connected to as a speech synthesizer (using Perfect Paul, which famously was the basis for Professor Hawking's voice) only talks at 9600bps. So we'll bitbang it!
oldvcr.blogspot.com
The KIM-1 that sounds like Stephen Hawking (or: "jitbanging" DECtalk)
My 1976 briefcase Commodore/MOS KIM-1, a 1 MHz single-board computer with a 6502 CPU and 1K of RAM, has learned to talk — with a familiar-so...
oldvcr.blogspot.com