Date: Tue, 23 Aug 94 17:24:41 -0400
From: dj AT ctron DOT com (DJ Delorie)
To: brzez AT dsiinc DOT com
Cc: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Re: Accsessing VGA directly with DJGPP

> I'm twidling around with some graphics algorithms and would like to use
> DJGPP to do my displays. I want to access video directly (VGA 320x200 at 256
> colors) for fastest possible speed. I really don't want to do this all in
> assembly but will if I have no other choice. So I'm wondering if direct access
> using djgpp is possible and if so then how? Any examples on accessing VGA 
> modes directly would greatly be appreciated. 

For standard VGA modes, you can use the int86() call to set the modes
through BIOS, and use <sys/farptr.h> and <pc.h> to access the memory
region and I/O ports.

Most of the tricky parts deal with bank switching for >64K video
buffers, and selecting card-specific modes.