Xref:	news2.mv.net comp.os.msdos.djgpp:4697
From:	Francisco Gochez <arcanix AT pop DOT erols DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Simplest way to access VGA memory
Date:	6 Jun 1996 19:14:24 GMT
Organization:	None
Lines:	22
Message-ID:	<4p7amg$pd0@news5.erols.com>
NNTP-Posting-Host:	as28s07.erols.com
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Here is the safest, easiest way that I have found to access the video 
memory:

#include <dpmi.h>
#include <malloc.h>

unsigned char *screenptr;

int main(void) 
 {
   screenptr = malloc(65536);
   __djgpp_map_physical_memory(screenptr, 65536, 0xA0000);    
.............

This sets up a pointer to the video memory area. (ex. screenptr[1] = 2 ; 
)
Of course, this will only work under DPMI 1.0 ( or CWSDPMI ). I am using 
it for a game I am working on, and it has always worked so far.

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