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From: niko@iastate.edu (Schuessler Nikolaus E)
Newsgroups: comp.sys.mac.programmer
Subject: Re: MC 68040 Compatibility Questions
Message-ID: <1991Mar17.234807.14271@news.iastate.edu>
Date: 17 Mar 91 23:48:07 GMT
References: <17535@crdgw1.crd.ge.com>
Sender: news@news.iastate.edu (USENET News System)
Organization: Iowa State University, Ames, IA
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>Does anyone have any opinions (or better yet, experience) about 
>compatibility problems with 68040 CPU's running standard Mac
>applications?  I'm asking this for a friend who is considering
>buying an add-on 68040-based accelerator to his SE30.  He is worried
>about the (reportedly somewhat different) floating-point implmentation
>of the 68040 versus the 68030 causing problems for applications.

Well, I am in no way an expert on 68040's, but I have done some reading
in Motorola's technical literature.  The difference in the floating point
implementation is that the 68040 doesn't implement all the 68881/2 functions
in hardware... The remaining functions are implemented as traps.  This means
they will run much slower (as someone else commented on one of these mac
groups).




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