Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site tikal.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!vax135!cornell!uw-beaver!tikal!dal
From: dal@tikal.UUCP (Don Ledford)
Newsgroups: net.micro.cbm
Subject: Re: Amiga - 68000 chip
Message-ID: <229@tikal.UUCP>
Date: Wed, 28-Aug-85 15:59:57 EDT
Article-I.D.: tikal.229
Posted: Wed Aug 28 15:59:57 1985
Date-Received: Fri, 30-Aug-85 09:28:42 EDT
References: <3429@garfield.UUCP> <916@vax2.fluke.UUCP>
Reply-To: dal@tikal.UUCP (Don Ledford)
Distribution: net
Organization: Teltone Corp., Kirkland, WA
Lines: 21
Summary: 
Organizatio: Teltone Corporation, Kirkland, WA

------
In article <916@vax2.fluke.UUCP> kurt@fluke.UUCP (Kurt Guntheroth) writes:
>The amiga uses the 68000 chip exactly because it is less expensive and the
>amiga does not require the 68010 extra capabilities of instruction restart.
>The 68000 and 68010 are directly compatible and if you want to speed
>everything up about 7-8%, you can just drop in a 68010 (assuming the 68000
>is in a socket of course).
>-- 

I'm a software type and don't have access to the amiga schematics, but
I would caution against replacing the 68000 chip with a 68010 until
you know for sure it doesn't effect the shared access to the video RAM.
It may be that access is arbitrated by monitoring the instruction
fetch activity of the CPU (during fetch the DMA has a free shot at
the video RAM).  The 68010 doesn't need to perform fetches for certain
types of code loops (hence the speed improvement); this may cause
unacceptable delays for the video circuitry.

Speculation only. 

Don Ledford