delorie.com/archives/browse.cgi   search  
Mail Archives: djgpp/1999/10/24/10:08:49

From: DavMac AT iname DOT com (Davin McCall)
Newsgroups: comp.os.msdos.programmer,comp.os.msdos.djgpp
Subject: Re: Just a few questions
Date: Sun, 24 Oct 1999 06:30:08 GMT
Organization: Monash Uni
Lines: 50
Distribution: world
Message-ID: <3812a5c7.3453113@newsserver.cc.monash.edu.au>
References: <7up2m7$pvc$1 AT ctb-nnrp2 DOT saix DOT net> <85cQ3.632$pD5 DOT 45821 AT dfiatx1-snr1 DOT gtei DOT net>
NNTP-Posting-Host: damcc5.halls.monash.edu.au
X-Trace: towncrier.cc.monash.edu.au 940746584 16481 130.194.198.138 (24 Oct 1999 06:29:44 GMT)
X-Complaints-To: abuse AT monash DOT edu DOT au
NNTP-Posting-Date: 24 Oct 1999 06:29:44 GMT
X-Newsreader: Forte Free Agent 1.1/32.230
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Reply-To: djgpp AT delorie DOT com

On Sat, 23 Oct 1999 05:55:16 GMT, "Damian Yerrick"
<web DOT poison AT pineight DOT 8m DOT com> wrote:

>> And then, since I'm used to 16bit programming, is
>> there any other important facts I should know about,
>> that is important in 32bit programming?  I do know
>> in 32bit programming the memory is a flat model,
>
>True. Technically, it would be called a "tiny" model.

Eh? It would be called the "flat" model. "tiny" model refers to data
and text being together in the same 64KB 16-bit segment. It's called
"tiny" only because of the limit on the total program size.

DJGPP does not impose that limit.

>> and there is no segments (except for the 4GB
>> segments) like there is in 16bit programming.
>
>There are still segments in DPMI programming if you
>want to access memory outside your program's private
>area, e.g. video RAM or the First Meg.

That's right. There are still segments. You don't have to deal with
them, except in cited circumstances (even then, you can avoid them by
using the "nearptr hack" but most people recommend you don't do this).

>> I know when one uses registers in 32bit modes,
>> you have to use eax, ebx, etc. and not ax, bx, etc.
>> but is there also like an IDEAL mode and
>> MASM modem in the DJGPP assembler?
>
>Modem? You want a serial library?

I suspect that was a typo, and that he actually meant "mode" (ie, is
there a MASM mode in the DJGPP assembler? - to which the answer is
no).

NASM is a good alternative though, as it supports the more familiar
Intel instruction syntax, and can be used in place of gas. Inline
assembly must always be AT&T syntax however.

I recently saw a project that was working on creating a gcc port which
used nasm as the backend, allowing intel style inline assembly. It
wasn't in a completely working state, however.

Davin.
__________________________________________________________
       *** davmac - sharkin'!! davmac AT iname DOT com ***
my programming page: http://yoyo.cc.monash.edu.au/~davmac/

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019