From:	krizz <krizz AT mailto DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Pointer to 0xA000
Date:	Wed, 10 Dec 1997 00:10:19 +0100
Organization:	LF.net GmbH, Internet Services, Stuttgart, Germany
Lines:	28
Message-ID:	<348DCFDB.6BED2450@mailto.de>
References:	<01bd0337$01ac5e00$390760c3 AT benjamir>
NNTP-Posting-Host:	p2-01.stuttgart.netsurf.de
Mime-Version:	1.0
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

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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