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From: pkr@maddog.sgi.com (Phil Ronzone)
Newsgroups: comp.arch
Subject: Re: IBM PC prehistory
Message-ID: <2773@odin.SGI.COM>
Date: 12 Jan 90 19:23:38 GMT
References: <1576@aber-cs.UUCP> <9308@cbmvax.commodore.com>
Sender: news@odin.SGI.COM
Organization: Silicon Graphics, Inc., Mountain View, CA
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In article <9308@cbmvax.commodore.com> daveh@cbmvax.commodore.com (Dave Haynie) writes:
>The MMU is certainly a difference when it comes to implementing UNIX on a
>680x0 system.  But that's an OS concern, it shouldn't have anything to do
>with an ABI standard.  That is, after all, Applications Binary Interface. 
>Under 680x0 systems, MMU code is supervisor (kernel) mode only; it can't be
>run at the user mode level under any circumstance. 


Not so. Page size and above all segment ARE visible to the binary.
Loadable libraries, shared memory see MMU characteristics as well
(or see the programmed characteristics of the MMU).


------Me and my dyslexic keyboard----------------------------------------------
Phil Ronzone   Manager Secure UNIX           pkr@sgi.COM   {decwrl,sun}!sgi!pkr
Silicon Graphics, Inc.               "I never vote, it only encourages 'em ..."
-----In honor of Minas, no spell checker was run on this posting---------------