peter@ficc.uu.net (Peter da Silva) (04/10/90)
In article <GRT23E1ccs@ficc.uu.net> korenek@ficc.uu.net (Gary Korenek) writes: > IMHO, a _really_ twisted microprocessor is the RCA 1802. No "CALL" > or "RETURN" instructions, for example. If you want subroutines, you > have to execute "CALL" code (that you have to include), and for the > subroutine to return, the subroutine has to execute "RETURN" code > (that you also must provide!). Awww, I like the 1802. 16 16-bit registers, any of which could be PC or SP, but no 16-bit load-and-store instructions. It really could do calls and returns, but only to coroutines by setting the PC. And it was a really neat processor for FORTH, because the Forth threaded call was *faster* than the Standard Call and Return Technique. This is getting off the subject of CP/M. Followups to comp.misc. (by the way, this is being posted from my Xerox 820 for the first time. I still don't have anything that can speak any protocols... :-<) -- _--_|\ `-_-' Peter da Silva. +1 713 274 5180. <peter@ficc.uu.net>. / \ 'U` \_.--._/ v