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From: mcdonald@uxe.cso.uiuc.edu
Newsgroups: comp.arch
Subject: Re: PDP-10 user I/O
Message-ID: <46500018@uxe.cso.uiuc.edu>
Date: 28 May 88 15:23:00 GMT
References: <21820@amdcad.AMD.COM>
Lines: 10
Nf-ID: #R:amdcad.AMD.COM:21820:uxe.cso.uiuc.edu:46500018:000:503
Nf-From: uxe.cso.uiuc.edu!mcdonald    May 28 10:23:00 1988


I also would like to see hardware manufacturers make it IMPOSSIBLE
for operating system writers to prevent use of IO, all instructions,
etc, by ALL programs. I find it frustrating to find many otherwise
lovely computers rendered useless to me by an operating system which
prevents me from writing programs the way I like. How hard would it
be to have a jumper on the CPU board that would circumvent the bits
in the PSW that prevent user-mode programs from doing IO and taking
interrupts?
Doug McDonald