Xref: news2.mv.net comp.os.msdos.djgpp:7050
From: alaric AT abwillms DOT demon DOT co DOT uk (Alaric B. Williams)
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Accessing graphics memory
Date: Sat, 10 Aug 1996 09:47:05 GMT
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Message-ID: <839670301.12614.1@abwillms.demon.co.uk>
References: <Pine DOT OSF DOT 3 DOT 91 DOT 960808131941 DOT 31475B-100000 AT bud DOT cc DOT swin DOT edu DOT au>
NNTP-Posting-Host: abwillms.demon.co.uk
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

John Joseph Newbigin <079519 AT bud DOT cc DOT swin DOT edu DOT au> wrote:

>I was thinking about the ways to access graphics video memory and it hit 
>me that it the video memory could be paged so that it is part of the data 
>segment then it can be accessed with a near pointer and still keep memory 
>protection.

>I have not tried any of the DPMI services in DJGPP so I don't know how 
>easy or hard this would be, or if it is possible at all, so I am 
>suggesting it here.  Does anyone know if this is possible and if so, how 
>to do it?

That used to be done by GO32 in the good old days before DPMI
compliancy was compulsory! It would load bankswapping drivers, and use
paging to create a linear memory 'alias' of screen memory, paging as
necessary!

>Newbs.

ABW


--
I have become... Comfortably numb...

Alaric B. Williams Internet : alaric AT abwillms DOT demon DOT co DOT uk
<A HREF="http://www.hardcafe.co.uk/Alaric/">http://www.hardcafe.co.uk/Alaric/</A>