Re: 6502, 65816 = RISC ?

[nathan@visi.com (Nathan Mates)]

In article <32142A65.409B@esis.vsnet.ch>,
Gilles Tschopp  <gilles.tschopp@esis.vsnet.ch> wrote:
>I would like to show a very interesting thing from the Western 
>Design Center home page.... 

   Don't believe what people tell you when they're trying to sell
you something.

>I found this sentence at bottom on this page 
>	http://www.wdesignc.com/new.html
>".... The 6502 has been identified by some, including 
>Microprocessor Report (12/90), as the first 8-bit RISC 
>microprocessor. ...."

   More like "well, this is the closest thing you'd get to RISC
in a 8-bit package, but it's still not up to par."

>It means that WDC claims that the 6502 is RISC ?????

   So what? Cigarette companies may claim that their product is not
addictive and not harmful. (Not that a claim of RISC is anywhere near
that level of lying or maliciousness). We've already stated the
_FACTS_ about what RISC means. Ignore them at your own peril:

RISC means:

1) Reduced instruction set. If you can do it with a few other
instructions, that instruction shouldn't be there. (e.g. increment/
decrement vs add/subtract of 1). 6502 fails.

2) Lots of registers, usually 16 or 32. 6502 has 3 that are useful.
Fails.

3) You can do the same operations (add, subtract) to any register.
6502 fails.

4) [Optional, but it's been a hallmark of pretty much all commercial
RISC chips] Pipelined execution. 6502 fails.

5) [Even more optional] Integer multiplication on chip. 6502 fails.

6) Designed with the RISC philosophy in mind. 6502 fails. [RISC wasn't
even around at the time]

   According to the technical definitions, the 6502 is NOT a RISC
chip. It may be close and a good attempt, but it is NOT one.

   If you believe everything you read online, I've got some good
swampland^H^H^H^H^H^H^H^H^H real estate to sell you. Real cheap.

Nathan Mates
--
<*> Nathan Mates http://www.visi.com/~nathan/      <*>
# What are the facts? Again and again and again-- what are the _facts_?
# Shun wishful thinking, avoid opinion, care not what the neighbors
# think-- what are the facts, and to how many decimal places?  -R.A. Heinlein