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Re: Second Sight again...
- Subject: Re: Second Sight again...
- From: bazyar@hypermall.com (Jawaid Bazyar)
- Date: 1995/07/13
- Newsgroups: comp.sys.apple2
- Organization: SuperNet Inc. (303)-296-8202 Denver Colorado
- References: <3taljo$rgq@nuscc.nus.sg> <3ti1qf$be0@news.mel.aone.net.au> <3tj7gm$duq@gap.cco.caltech.edu> <3tudbm$p4g@news-2a.csn.net> <3u03ct$bbd@gap.cco.caltech.edu>
Todd P. Whitesel (toddpw@liquefy.ugcs.caltech.edu) wrote:
: bazyar@hypermall.com (Jawaid Bazyar) writes:
: > SHR emulation code scans the frame buffer backwards (you don't want to know)
: Decrement-and-branch-if-non-zero instructions. gotta love em.
Not djnz, actually. More like the CPD block transfer instruction.
That lets me copy data, and update _three_ pointer register sets
all in one instruction and 12 clocks.
--
Jawaid Bazyar | Like UNIX? Like your Apple IIGS? Then ask
Procyon, Inc. | me about GNO/ME for the Apple IIgs!
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