Xref:	news2.mv.net comp.os.msdos.djgpp:6220
From:	brucef AT central DOT co DOT nz (Bruce Foley)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: VESA 2.0 and DJGPP oddities....
Date:	Sun, 21 Jul 1996 01:32:12 GMT
Organization:	Internet Company of New Zealand
Lines:	27
Message-ID:	<4ss4mu$agt@status.gen.nz>
References:	<4smlhp$d76 AT dfw-ixnews6 DOT ix DOT netcom DOT com>
NNTP-Posting-Host:	brucef.central.co.nz
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

bushwick AT ix DOT netcom DOT com (Peter Rittwage) wrote:

>I recently began converting over some code I had from 320x200 mode 11h to 
>VESA 2.0 mode 101h (640x480x256).   I used the demo code from VBETEST.C which I 
>found on someone's web page.

>I modified the code, which is pretty straighforward, BUT....

>If you remove the line that plots a single pixel in the upper left corner before doing 
>anything else to the buffer, it completely resets the computer.   What's up with this?   
>Plotting a pixel at 0,0 makes VESA work?


In the pixel plot routine, it may also be setting a selector to
address video memory.
When you removed the pixel plotting, you may have removed that also.

Then, when you addressed the buffer, the selector was not set, and you
said goodbye to the system...

Just a guess, but I'd check it out.

Bruce.

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