Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-lcc!ames!mailrus!tut.cis.ohio-state.edu!rutgers!bpa!cbmvax!vu-vlsi!devon!shockeye!hermit
From: hermit@shockeye.UUCP (Mark Buda)
Newsgroups: comp.sys.ibm.pc
Subject: Paradise VGA Plus undocumented video modes
Keywords: how do I do it?
Message-ID: <247@shockeye.UUCP>
Date: 13 Dec 88 19:45:58 GMT
Reply-To: hermit@shockeye.UUCP (Mark Buda)
Organization: The Lab Rats
Lines: 19

I recently downloaded a file from a local bulletin board (interrup.arc on
simtel20) that is chock full of wonderful information on assorted
interrupts. Imagine my puzzlement when I read (under the BIOS set video
mode int) that my Paradise VGA Plus board has a 640x480 256-color mode!
I looked in the little booklet you get with the board, and there's not
mention of it. It's not advertised anywhere I've seen either. So I played
with it. 640 x 480 x 256 > 128K. Problem. How do you get access to the
bottom half of the screen in this mode? I fiddled with the mysterious
"Paradise Registers" and discovered that by putting 0x70 (I think) in
Paradise register #2, I could write to the bottom of the screen BUT it also
crashed the machine. If I disable interrupts, it doesn't crash the machine.

Why do I have to disable interrupts to do this? What is the REAL magic
procedure I need to get at the second 128K of video RAM? Inquiring minds
want to know.
-- 
Mark Buda / Smart UUCP: hermit@shockeye.uucp / Phone(work):(717)299-5189
Dumb UUCP: ...rutgers!bpa!vu-vlsi!devon!shockeye!hermit
I hate this $%$@%!$@%!@$%@#$@!% machine.
"A little suction does wonders." - Gary Collins