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Mail Archives: djgpp/1997/12/10/18:17:21

From: Ryan McGee <don't AT spam DOT me>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Pointer to 0xA000
Date: Wed, 10 Dec 1997 16:16:16 -0600
Organization: InLink Communications Company
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References: <01bd0337$01ac5e00$390760c3 AT benjamir> <348DCFDB DOT 6BED2450 AT mailto DOT de>
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To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp

What exactly does _dos_ds do though?  Whats the difference between a selector and
a sector?

Ryan
________________________________________________________________________
If you feel the need, you can e-mail me at RDM AT inlink DOT com

krizz wrote:

> hi
> a simple and good method is to copy a buffer
> which is 0xffff size great to 0xa0000. you simply
> write all the stuff (putpixel,...) into the buffer
> and copy it via 32bit(0xffff/4=0x3fff) to the
> vga addr.
>
> here an example:
>
> short video=__dpmi_segment_to_descriptor(0xa000);
> unsigned char buffer=malloc(0xffff);
> _movedatal(_my_ds(), (unsigned int)buffer, video, 0, 0x3fff);
>
> krizz
>
> Olmeca wrote:
>
> > I wanna have a pointer to the address 0xA000, but in Djgpp it's a problem.
> > e.g.: unsigned char *vga=0xA000 (this doesn't work, cause of protected
> > mode)
> > in the FAQ's is something about the macro: _dos_ds, but I don't know how to
> > use it...
> > Anybody help?
> >
> > chromes AT hotmail DOT com



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