Path: utzoo!attcan!ncrcan!becker!censor!comspec!tvcent!lethe!torsqnt!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!wuarchive!husc6!m2c!wpi!ggray
From: ggray@wpi.wpi.edu (Gary P Gray)
Newsgroups: comp.sys.apple2
Subject: Re: why wait for wdc or asic? 32-bit 6502's already exist!!!
Message-ID: <12725@wpi.wpi.edu>
Date: 7 May 90 01:33:12 GMT
References: <9005061648.AA00952@apple.com>
Reply-To: ggray@wpi.wpi.edu (Gary P Gray)
Organization: Worcester Polytechnic Institute, Worcester ,MA
Lines: 37

In article <9005061648.AA00952@apple.com> $CSB211@LSUVM.BITNET (mark orr) writes:
>anyway, the title of this article is correct. thirty-two bit
>6502's already exist (and have existed since late '87)
>
>the chip that i'm referring to is the arm - acorn risc machine.
>it is a risc chip with an instruction set deliberately designed
>around the 6502 - actually the instruction set is a superset of
>the 6502. it was designed for the archimedes a310 computer in
>england, which was previewed in the october 1987 issue of byte.

I know two hardware hackers who had gotten ahold of the specs for this thing. 
They were mighty impressed(a 32 bit risc processor for ~$35) Now, had Apple
used this (or is going to use this) for a new //, watch out! I don't know
offhand what the MIPS for this chip are, but it is certainly fast enough for
any application a low to mid level machine would do.

As for it's 6502ish design, I'd say they took inspiration and not much else
from the chip (actually, one of the aforementioned hardware hackers jokingly
referred to the 6502 as a slow RISC machine with few registers :). The
memonics are not taken directly from the 6502 to the best of my recollection
(they are your generic low level assembly commands, load, store, and, or etc.)

  There is a few weird things, like each instruction has a conditional test in
it.  From what I understand, you have instructions like "transfer R1 to R2 if
z bit is set."  It's a 32 bit processor, but it's address range is 28 bits (oh
gee, *how* would I ever fit my programs in ) 

UN*X has been developed for this system, so there are development tools.  Now,
should Apple choose to develop with this and build up a simple and straight
forward hardware base...  

Anybody have info on the Acorn computer that uses this?
-- 
-- WARNING!!! The above opinions may be HAZARDOUS or FATAL if swallowed!!! --
 "My mind is going... I can feel it...    |  Gary Gray -- ggray@wpi.wpi.edu
  I can feel it..."                       |  GEnie: GGRAY6
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