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From: jb10320@uxa.cso.uiuc.edu (Jawaid Bazyar)
Newsgroups: comp.sys.apple2
Subject: Re: sideaffect of MVN/MVP instruction
Message-ID: <1991May30.162912.17573@ux1.cso.uiuc.edu>
Date: 30 May 91 16:29:12 GMT
References: <3644@kluge.fiu.edu> <1991May30.025443.428@nntp-server.caltech.edu>
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toddpw@nntp-server.caltech.edu (Todd P. Whitesel) writes:

>It has
>been speculated that the MVP/MVN instructions were originally different and
>somewhat useless instructions, and that Mensch hacked in the move code at
>the last minute -- this would easily explain the 7 cycle/byte timing (the
>instruction is fetched repeatedly for each byte copied -- blech!) and the
>side effects. 

   Might the fetch of the instruction over and over be a result of making
the MVP/MVN instructions interruptable?

>Besides, it took them long enough to get the original 65816
>ready (the GS ROM 00 was tested with 65802's because they were all that
>was available -- evidence of this is buried in the softswitch list in the
>firmware ref).

   Amen- it was what, almost three years after the Apple //x rumors started
that we finally got the GS? 

--
Jawaid Bazyar               |  "Twenty seven faces- with their eyes turned to
Graduated!/Comp Engineering |    the sky. I have got a camera, and an airtight
bazyar@cs.uiuc.edu          |     alibi.."
   Apple II Forever!        |  I need a job... Be privileged to pay me! :-)