Path: utzoo!mnetor!uunet!cbmvax!daveh
From: daveh@cbmvax.UUCP (Dave Haynie)
Newsgroups: comp.sys.amiga
Subject: Re: 68030-based PC's
Message-ID: <3540@cbmvax.UUCP>
Date: 28 Mar 88 22:47:27 GMT
References: <1505@puff.cs.wisc.edu>
Distribution: na
Organization: Commodore Technology, West Chester, PA
Lines: 20

in article <1505@puff.cs.wisc.edu>, avery@puff.cs.wisc.edu (Aaron Avery) says:

> Over twice? This must be only in cases of 0ns internal MMU translation. The
> '030 can have a 2-clock memory cycle, while the '020 is limited to a 3-clock
> memory cycle, so there's this advantage up front. 

The '020 usually ends up with a 4 clock memory cycle if you've got that MMU in
there.  But the '030 also has a neat 1-clock burst mode; the CPU can't eat
memory at that speed, but it can be used for cache fills and things like that.
It does require some external circuitry and certainly some design cleverness,
though the 2-clock memory cycle is going to require some design cleverness as
well if you aren't willing to spend a small fortune for ridiculously fast
memories (at the price of memory chips these days....).

> Aaron Avery (avery@puff.cs.wisc.edu)

-- 
Dave Haynie  "The B2000 Guy"     Commodore-Amiga  "The Crew That Never Rests"
   {ihnp4|uunet|rutgers}!cbmvax!daveh      PLINK: D-DAVE H     BIX: hazy
		"I can't relax, 'cause I'm a Boinger!"