There are lots of things one CPU could do more simply than another, but,
normally, there were others that went the other way. I remember, back in '80 or
so, demonstrating that the 4 MHz 6502 was considerably faster and more code
efficient than the 8 MHz 68000. This was, of course, because the 8 MHz 68K had
to fetch two words just to get its opcode, though it didn't take long to execute
it once the opcode and operands were in place.
The key, back in the "old days" was to know each of the available
microprocessors well enough to pick the right one in the first place. For
almost any task, there was one that would do the most critical tasks more
elegantly and efficiently than some other. In most cases, it didn't matter
anyway.
Dick
----- Original Message -----
From: "Cameron Kaiser" <spectre_at_stockholm.ptloma.edu>
To: <classiccmp_at_classiccmp.org>
Sent: Sunday, August 19, 2001 1:05 AM
Subject: Re: SemiOT: Mourning for Classic Computing
> > with U or S for that matter). On the 6809 you can transfer values between
> > any 2 registers of the same size. On the 6502 you can't even transfer
> > between X and Y without destroying the accumulator contents (IIRC).
>
> Of course you can!
>
> unused_zp = $02
> stx unused_zp
> ldy unused_zp
>
> ;-)
>
> --
> ----------------------------- personal page:
http://www.armory.com/~spectre/ --
> Cameron Kaiser, Point Loma Nazarene University * ckaiser_at_stockholm.ptloma.edu
> -- The earth is like a tiny grain of sand, only a lot heavier and
bigger. -----
>
>
Received on Sun Aug 19 2001 - 08:26:19 BST