Xref: news-dnh.mv.net comp.os.msdos.djgpp:2000
Path: news-dnh.mv.net!mv!news.sprintlink.net!tank.news.pipex.net!pipex!news.mathworks.com!news.duke.edu!agate!newsxfer.itd.umich.edu!caen!uwm.edu!math.ohio-state.edu!cs.utexas.edu!news.cs.utah.edu!sal.cs.utah.edu!larsen
From: larsen AT sal DOT cs DOT utah DOT edu (Steve Larsen)
Newsgroups: comp.os.msdos.djgpp
Subject: DPMI question
Date: 11 Sep 1995 06:46:55 GMT
Organization: University of Utah Computer Science Department
Lines: 26
Reply-To: larsen AT sunset DOT cs DOT utah DOT edu
Nntp-Posting-Host: sal.cs.utah.edu
To: djgpp AT sun DOT soe DOT clarkson DOT edu
Dj-Gateway: from newsgroup comp.os.msdos.djgpp

Hi,

This is probably a stupid question to most, but I have looked everywhere
for info and haven't found exactly what I need, so here goes...

I am writing some VESA 2.0 routines.  One thing I need to be able to
do is access a linear segment of memory (a linear framebuffer).  I have
figured out how to get the physical address from the VBE, allocated a 
selector, and set the base and limit of the selector as described in 
numerous places.  Now I need to figure out how to use all this info
to do what I want :)  Basically, I want to do a memcpy from my
offscreen buffer to some mapped memory and have it appear on the
screen (either in C or asm, either is fine).  Also, I would rather
not use the nearptr's hack.  Any help would be greatly appreciated.

Thanks in advance,

--
Steve Larsen
larsen AT sunset DOT cs DOT utah DOT edu

P.S.  Another quick one.  Today while trying to get this working,
	I was hitting an interesting problem.  I was getting a
	protection fault while loading a segment register (es).
	Are the segment registers somehow protected while in
	protected mode?