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From: rex@otto (Rex Jolliff)
Newsgroups: comp.sys.atari.st
Subject: Re: electronics help sought
Message-ID: <891@otto.lvsun.com>
Date: 10 Apr 89 00:22:55 GMT
References: <13050@watdragon.waterloo.edu>
Sender: rex@otto.lvsun.com
Reply-To: rex@otto (Rex Jolliff)
Distribution: comp
Organization: The Las Vegas Sun.
Lines: 22
In-reply-to: bjhicks@trillium.waterloo.edu (Barbara Hicks)

In article <13050@watdragon.waterloo.edu>, bjhicks@trillium (Barbara Hicks) writes:
>
> ...
>perform a range check for each User Data or User Instruction fetch.  I would
>like to have two separate ranges, one for Data and one for Instructions.
>Ideally I would like to check all 24 address lines, but I would settle for
>just the upper 16.  ...
>-- Barbara (bjhicks@trillium)

I would suggest using a 68451 mounted on a daughterboard with the CPU, but
I don't know what kind of conflicts you would run into between the 68451
and the atari MMU chip.  I think with some careful programming and a well
planned hardware interface, this could work and provide memeory protection
for the ST.

								Rex.
--
Rex Jolliff  (rex@otto.lvsun.com, {convex, texsun, mirror}!otto!rex)
The Sun Newspaper -            |Disclaimer:  The opinions and comments in
Nevada's Largest Daily Morning | this article are my own and in no way
Newspaper                      | reflect the opinions of my employers.
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