From:	Vinzent Hoefler <JeLlyFish DOT software AT gmx DOT net>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: DMA access
Date:	Thu, 27 Jan 2000 22:24:52 +0100
Organization:	JeLlyFish software
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"Julian Rolon" <jrolon AT alpha DOT telecom-co DOT net> wrote:

>I am very confused cause function is returning segments like 1FC2 and i need
>to pass physical address to a chip, so what is the physical addres of a
>segment like this??

Real memory adressing mode:

Segment*16+Offset = physical address

(offset is zero you can ignore that and this turns into a simple *16 =
<<4)

So a macro like this would be perfect:

#define PHYSICAL_ADDRESS(realseg) realseg<<4


Vinzent.

-- 
Real programmers don't comment their code.  It was hard to write, it
should be hard to understand.

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