accessing video RAM: how advisable is it?

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#5254

From: Tom Reingold
Date: Sat, 16 Mar 1991 20:53

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Are PC's running DOS more compatible with IBM video cards these days
than they were when MS-DOS came out?  Years ago, you were asking for
trouble if you wrote directly to video RAM because many cards had their
display buffers at various addresses.  Is this no longer true?  I'd
like to know because it would be nice if the product I am developing
didn't need to care.

Also, are the two addresses still the only ones to worry about?  There
is one for monochrome and one for color, including CGA, EGA and VGA.
--
        Tom Reingold
        tr@samadams.princeton.edu  OR  ...!princeton!samadams!tr
        "Warning: Do not drive with Auto-Shade in place.  Remove
        from windshield before starting ignition."

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From: tr@SAMADAMS.PRINCETON.EDU (Tom Reingold)
Newsgroups: comp.os.msdos.programmer
Subject: accessing video RAM: how advisable is it?
Message-ID: <9103162053.AA02053@samadams.Princeton.EDU>
Date: 16 Mar 91 20:53:39 GMT
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