Path: utzoo!attcan!uunet!husc6!mailrus!purdue!decwrl!ucbvax!ULKYVX.BITNET!RWMIRA01
From: RWMIRA01@ULKYVX.BITNET (Rob Miracle)
Newsgroups: comp.graphics
Subject: RE:VGA Card with C
Message-ID: <8806201432.AA07849@jade.berkeley.edu>
Date: 20 Jun 88 14:26:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: University of Louisville
Lines: 20

First a brief description of VGA.  VGA has all of the CGA, and EGA modes.  It
also supports a 640X480 16 color mode and a 320X200 256 color mode.  There is
also a 640X480 2 color mode.  The 640X480 modes use a bit map identical to EGA
expept for it being 640X480 instead of 640 X350.  The 256 color mode is
addressed at 0xA0000000 and one byte = one pixel.  So you can access any pixel
by 320*Y+X for the Offset and a Segment of 0xA000.  The graphics mode here is
0x13.

A really good book to get hold of if you want to learn how to do this is:

Programmer's Guide to the PC & PS/2 Video Systems, Richard Wilton, Microsoft
Press, ISBN 1-55615-103-9, Library of Congress QA76.8.I2594W55, 1987.

It details the VGA, MCGA, EGA, CGA, MDA, and Herculeas cards.  Most of the
code examples are in MASM, but most people would not have a problem with it.

Rob Miracle
Programmer/Analyst-II
University of Louisville
RWMIRA01@ULKYVX.BITNET