Re: Opcode Instruction Question

[mjmahon@aol.com (Michael J. Mahon)]

Bryan Parkoff asked:

>    Do you think that CISC uses a lot of instructions that might take little
>longer to process however RISC uses a less of instructions that might
>increase great performance.  I think that 65816 is like CISC while 68K is
>like RISC.  What do you think?

Wow.  This is tantamount to flame bait!  ;-)

The 68K family is more like a VAX than anything else, and is _definitely_
in the CISC camp.  The debates are endless, but a pretty good test is
whether there are operations that work on a register with a memory
operand (as opposed to just another register operand).

RISC machines are sometimes called LOAD/STORE machines, because
the only instructions that reference memory are LOAD and STORE
instructions.  All data manipulation instructions are register-to-register,
typically producing a result in a third register.

Read some of the _extensive_ literature on this topic--some is quite
enlightening, and some is merely confusing.

BTW, there is a good case for Seymore Cray inventing the first RISC
architecture--the CDC 6600.

-michael

 Email:  mjmahon@aol.com
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