From: Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: DOS fall calls.
Date: 18 Sep 2001 12:21:19 GMT
Organization: Aachen University of Technology (RWTH)
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Brian Smith <graywolf DOT smith AT virgin DOT net> wrote:
> Hi.
> I have written and used a number of assembly langage programs that use 16
> and 32bit graphics. In these I make a direct far call to a DOS address to
> execute video bank switching.

The best idea is to avoid this altogether, by using linear framebuffer
mode.  No bankswitch at all, thus no speed problems.

> Any one how I can make a fall call from a ASM function? Using the DOS int
> call is too slow.

You could, in principle, do a __dpmi_simulate_far_call or whatever the
precise libc function name is. But it'd still weigh in the protected
-> real and back mode switching, unless your VESA BIOS has a protected
mode bankswitch call, too.


-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.