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From: master AT micro DOT internexus DOT net (Laszlo Vecsey)
Newsgroups: comp.os.msdos.djgpp
Subject: Pointer to video memory (0xA000)
Date: 18 Dec 1995 20:31:19 GMT
Organization: The Internet Nexus
Lines: 26
Message-ID: <4b4j2n$9mf@micro.internexus.net>
NNTP-Posting-Host: micro.internexus.net
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

Help! I get a general protection fault when accessing a pointer to video memory.

In Borland C++ I'm used to putting pixels to the screen as follows:

	unsigned char far *videomemory = (unsigned char far*)(0xA0000000);
	videomemory[320*y+x] = color;

I've found the following code in DJGPP to invoke VGA 320x200x256 just fine:

	asm("movl $0x13, %eax
             int $0x10
            ");

Unfortunately, DJGPP complains about the far keyword so I had to remove 
it in order to get my program to compile. When I run the program i get a 
general protection fault!

Any help would be appreciated..

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