From: "Stefan Viljoen" <Stefan_Viljoen AT excite DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: assembler probs
Date: Fri, 23 Mar 2001 19:44:15 +0200
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Michael Duxbury <M DOT R DOT Duxbury AT btinternet DOT com> wrote in message
news:99dc06$p3b$1 AT uranium DOT btinternet DOT com...
> I am trying to compile this but get a slight problem with the hello:   db
> void drawline(int x1,int x2, int y, char color)
> {
>   asm (" movb %ax , 0xa000");
> }
>
> Anyone help me out please?

If you want to use the above to access video RAM, it won't work (I think!)
What you need is a
descriptor to video RAM - you cannot use segment addresses in a segment
register to attempt to access video RAM like you can do in real mode. See
http://home.intekom.com/rylan/ for some simple assembler examples (using
NASM) of how to access 320x200x256 VGA at the VGA video segment under DJGPP
+ NASM. (NASM is a freeware assembler that accepts intel syntax assembly and
outputs DJGPP compatible COFF format object files that DJGPP can link and
use).

Regards,

Stefan Viljoen
F/EMS Dispatcher
Potchefstroom F/EMS
South Africa
http://home.intekom.com/rylan/