My home made one that I got working in 1981. A friend had built a machine around a 6800 and I had used the 6800 during a vacation job at Ferranti. The single in

My home made one that I got working in 1981. A friend had built a machine around a 6800 and I had used the 6800 during a vacation job at Ferranti. The single index register of the 6800 was a pain. One was always swapping indexes between X and RAM. Should I build a 6800 machine and suffer? The 68000 was being talked about and was going to be a lovely machine for assembler programmers, somewhat like the IBM360. But that could be a long wait for a processor which might be beyond my budget at first. So I went with the 6809. It was enough of an improvement over the 6800 to be bearable and available and reasonably priced. (The 6502 had two index registers, which was nice, but they were 8 bit, and I had ambitions to write a Lisp for my machine and would certainly want 16 address registers.)