Date:	Tue, 30 Jan 96 20:52:44 EST
From:	"William Parsons Newhall, Jr." <NEWHALL AT american DOT edu>
Organization:	The American University
Subject:	Re: Fastest way to access VESA 2.0 linear frame buffer?
To:	Kevin Baca <kbaca AT skygames DOT com>, DJGPP Mailing List <djgpp AT delorie DOT com>

In using a main memory (dare I say "virtual") frame buffer, do you have
a timer driven interrupt requesting a screen copy N times per second, or
do you only update the screen after something has been drawn(like after a
polygon fill or line draw)?

The idea of having a fast, automatic frame buffer intrigues me.  If it were
not for the address translation problem, one could use DMA transfer to make
it go even faster...

Thanks for the tip--I actually came across an old post describing the
"map the memory, allocate a selector, use farpoke" approach just after I
posted my question.  I have run into problems with my code, and with
testvbe.c which I got off of delorie.com.  After I have switched into
a mode and written a single pixel to the display(this is with testvbe.c)
my machine locks up.  With my code, none of the linear mapped 0x4XXX modes
are supported(my code checks to see if a mode is supported before it switches
into it)I think this could be a bug with UNIVBE or with the hardware of my
Hercules Dynamite Pro graphics card.

Thanks again for the tip...

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