From: James Tsillas <jtsilla AT ccs DOT neu DOT edu>
Date: Mon, 16 Oct 1995 21:49:19 -0400
To: djgpp AT sun DOT soe DOT clarkson DOT edu
Subject: Setting the video screen start for a VESA drv


Hi,

I'd like to write a program which allows a pair of independent video
pages (to allow page flipping for animation).

What is the recommended way of doing this. I noticed that the vesa
driver (built in to go32?) has support for an int 0x10 function numbered
0xfffc which calls handlers to run function 0x074f (int 0x10) in the
vesa driver.

Well, I've tried this and it doesn't work. I suspect the units I am
using are wrong and indeed it looks like a bug since the inputs to this
0xfc function are in screen coordinates (pixels?) while the vesa driver
expects an offset in memory granularity units.

Has anyone managed to do this? What technique have you used?

For example, I'd like to have a pair of 640x400 screens (one starting at
the normal place and the other starting at the next addressable point in
memory past the first).

Thanks,
-Jim.