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- From: kludge@hardy.u.washington.edu (Kludge)
- Newsgroups: rec.games.programmer
- Subject: Re: MCGA 320x400x256
- Message-ID: <1992Nov22.083944.17164@u.washington.edu>
- Date: 22 Nov 92 08:39:44 GMT
- Article-I.D.: u.1992Nov22.083944.17164
- References: <1992Nov21.195314.21119W@skylark.edb.tih.no>
- Sender: news@u.washington.edu (USENET News System)
- Organization: University of Washington, Seattle
- Lines: 34
-
- In article <1992Nov21.195314.21119W@skylark.edb.tih.no> thomash@edb.tih.no writes:
- >!
- >
- >I've heard there is a standard MCGA 320x400x256 mode available on all VGA cards. Is this
- >true, and if so -
- >
- >1) What mode-number is it?
- >2) How is the screen organized (bitmap/bitplanes)?
- >3) Where must I write to change which bitplane/screen area to write to/read from?
- >
- >Thanks a lot -
- >
- >Thomas Hagen
- >thomash@edb.tih.no
-
- Well... it's not exactly a standard mode. For that matter, it's not a
- mode at all - it's just a tweaked set of video parameters. For that reason,
- there isn't a mode number for it. The screen is organized into... well...
- byteplanes, I guess. One byte corresponds to four pixels - the pixel number
- (or numbers - more than one can be selected) is selected through a register.
- This sounds confusing - a much better explanation than I'm capable of went
- by a few posts ago.
- I'd suggest you pick up xlib04.zip off wuarchive.wustl.edu in
- pub/MSDOS_UPLOADS. It's a great library of routines for tweaked VGA modes.
-
- ...by the way, there is one annoying "feature" of some tweaked modes - they
- confuse monitors. Sometimes they'll click and hum for a moment, or lose
- the hold on the picture so you need to turn them off and on again. Also,
- in some tweaked modes (including 320x400) the picture is not the full
- vertical height of the screen, so it needs to be adjusted. Kind of
- annoying, but it works.
-
-
- --Kludge
-