Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!usc!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!aplcen!uunet!unsvax!uns-helios!davidg
From: davidg@uns-helios.nevada.edu (DAVID GONZALES)
Newsgroups: comp.sys.ibm.pc
Subject: VGA programming woes
Message-ID: <1243@unsvax.NEVADA.EDU>
Date: 14 Feb 90 20:40:28 GMT
Sender: news@unsvax.NEVADA.EDU
Reply-To: davidg@uns-helios.uucp (DAVID GONZALES)
Distribution: usa
Organization: Univ of Nevada System Computing Services - Las Vegas
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References:

hi,
	I am trying to write a program that will program a Orchid VGA card in
a non-DOS, non-INTEL environment (ie - a 68000-based system). I have been using
the Input/Output ports of the VGA card but have been unable to set the mode. Or
I should say that I think that I am changing the mode correctly but I am getting
no video to the screen. I have been using a 386-based DOS machine as a test base
but after setting the registers the screen goes blank and I need to use a MODE 
CO80 command to reset the card back to normal. My question is: Is there a trick
to setting the mode via I/O calls or is there a register that I am missing (or
am i failing to set a certain bit in the register(s)). I have the Technical
Reference Manual (from TSENG) that gives me all the register contents for each
of the modes that the card supports but I do not have much information about
programming the card (they use the BIOS!). Thanks.

david a. gonzales
ERC/UNLV