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in article <9795@cit-vax.Caltech.Edu>, wetter@cit-vax.Caltech.Edu (Pierce T. Wetter) says:

>>> For instance the 6502 can do every 
>>> instruction in one clock cycle, while the 68000 can take up to 70.

>> Many 6502 instructions are >1 cycle long, as a glance at any 6502 programming
>> manual will quickly confirm.  The true speed of any processor is

>     Ooops, sorry. I meant many 6502 instructions take ~ 1 cycle. I obviously
> didn't expect a multiply to run in one cycle.
> Pierce

Well, no problem, the 6502 doesn't have a multiply instruction.  I think 
there's a little mixing of ideas here.  Without wait states, the 6502 takes 
only 1 clock cycle for each bus access.  By contrast, a 68000 takes 4, a
68020 takes 3, and a 68030 takes 2 (the IIx and SE/30 both have wait states).
Bus access is only part of it, though.  As far as actual instructions go,
the 680x0 chips can take 60 or more clock cycles to do a multiply.  The 
6502's longest instruction takes around 7 clocks, but it's 32 bit multiply
routine will undoubtedly take longer at the same clock frequency than the
68030.  Perhaps a RISC processor at the same clock frequency can execute one
whole reasonable instruction in one cycle, and finish such a multiply faster
than the 60 clocks it might take the 68030.  The bottom line is who gets the
most actual work done in a particular chunk of time.  In some cases, it may
even be the 6502 that wins (I can think of one case it beats the 68000 at
1/2 the clock speed), but for the most part, don't count on it.

-- 
Dave Haynie  "The 32 Bit Guy"     Commodore-Amiga  "The Crew That Never Rests"
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              Amiga -- It's not just a job, it's an obsession