Date:	Sun, 26 Feb 95 14:05:57 EST
From:	"William Parsons Newhall, Jr." <NEWHALL AT american DOT edu>
Organization:	The American University
Subject:	Accessing VESA SVGA Frame Buffer
To:	djgpp AT sun DOT soe DOT clarkson DOT edu

Thanks to those who gave me advice on how to switch graphics modes using
DJGPP and go32_dpmi_simulate_int.  I am now able to switch into any VESA
mode and retrieve information about the mode with no problems, however,
I am a little confused about how I can access the frame buffer.

According to the DJGPP FAQ 1.00,"graphics doesn't work in dpmi mode." The FAQ
goes on to say that,"In non-dpmi mode the entire graphics video memory is
mapped 1:1 starting at 0xD0000000." Am I correct in assuming that,since my
mode switching and mode information retrieval functions use go32_dpmi functions
that I cannot access the frame buffer directly? Are there any non-dpmi based
mechanisms I can use to call real mode interrupts and pass buffers from DOS
conventional memory? Is there any way I can access the frame buffer(or the
64K DOS window into it at A000:0000) under dpmi?

Much thanks,

William Newhall

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