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Mail Archives: djgpp/1997/08/07/16:52:16

From: Mark Slagell <bald_soprano AT geocities DOT nospam DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Simple (I hope) VGA question
Date: Thu, 07 Aug 1997 09:08:55 -0500
Organization: the well-basically society
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Message-ID: <33E9D6F7.7BDF@geocities.nospam.com>
NNTP-Posting-Host: dial40.ppp.iastate.edu
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To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

Apparently after setting one of the 16-color screen modes, you have
direct access via video memory only to the first color plane.  So a
dosmemput() to 0xa0000 can give you a coarse monochrome image.  Is there
a way to 'select' another plane so it can be filled the same way?

All the info on VGA I've found on the web concerns itself with mode-x
and doesn't help here, except for one document that described modifying
individual pixels in mode 0x0d.  I honestly couldn't get my little brain
to grasp that explanation, which involved lots of diddling with the VGA
ports, but what I'm trying to do ought to be simpler than that anyway,
just throwing prepared images at the screen without regard to what's
already there.

I'd post this to comp.sys.ibm.pc.hardware.video too but there don't seem
to be programmers hanging around there.

-- 
"There is no theory.  You have merely to listen.  Fantasy is the law." 
  -- Claude Debussey

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