That was particularly "clean" processor compared to RCA Cosmac or PIC18c64. Dirtiness means overcoming some handicaps of shitty processor.

Yes. I made this crap 30 years ago, and now it needs some tuning. What were the assembler and programmer? No clue or recollection. https://github.com/timonoko/Seinakello/blob/master/seven3.as...