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From: mcdonald@aries.scs.uiuc.edu (Doug McDonald)
Newsgroups: comp.arch
Subject: Re: Coprocessors
Message-ID: <1991Mar31.025146.3531@ux1.cso.uiuc.edu>
Date: 31 Mar 91 02:51:46 GMT
References: <1991Mar27.123720.3992@decvax.dec.com> <2892@megatek.megatek.uucp> <10501@exodus.Eng.Sun.COM>
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>|> In <2892@megatek.megatek.uucp> mark@megatek.UUCP (mark thompson)
>|> writes:
>|> 
>|> >Whenever I read architecture manuals for (eg. the Moto 68000 series),
>|> >they invariably support several coprocessors. Also invariably, one of
>|> >those coprocessors is for floating point.
>|> ...
>|> >Has anyone tried to do something wonderful with one of the undedicated
>|> >coprocessors, examples of wonderful being I/O channel controllers or a
>|> >business instruction set?
>|> 
>
Certain LSI PDP-11 had (have?) business coprocessors that work with them.  

Certain other DEC LSI cpus (i.e. VAX) have the business instructions,
or some of them, emulated in software, because it was faster :-).


I doubt that that a business instruction set has quite the regularity of
the major part of a FPU.

Doug McDonald