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From: chewy@apple.com (Paul Snively)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Reforming Mac Programming
Message-ID: <7451@goofy.Apple.COM>
Date: 29 Mar 90 18:06:08 GMT
Sender: usenet@Apple.COM
Organization: Apple Computer, Inc.
Lines: 29
References:<13828@eagle.wesleyan.edu> <5492@okstate.UUCP> <1169@ra.cs.Virginia.EDU> <261189c1.4ce@polyslo.CalPoly.EDU>

In article <261189c1.4ce@polyslo.CalPoly.EDU> rcfische@polyslo.CalPoly.EDU 
(Raymond C. Fischer) writes:
> >68020 instructions that are not available on the 68000 could also
> >be emulated by using the "illegal instruction" trap but I don't know
> >if it would be worth doing.
> 
> Not possible.  In addition to a few new instructions, the 68020
> also has new addressing modes which do not generate illegal instruction
> traps, but rather just cause general mayhem when used on a 68000.
> 
> 
> Ray Fischer
> rcfische@polyslo.calpoly.edu

To make matters worse, the exception stack frame is different between the 
68000 and 68020, as anyone who's ever worked on a Mac debugger knows. ;-)

__________________________________________________________________________
                                Paul Snively
                      Macintosh Developer Technical Support
                             Apple Computer, Inc.

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Just because I work for Apple Computer, Inc. doesn't mean that I believe 
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__________________________________________________________________________