Message-Id:	<199703221655.RAA19061@magigimmix.xs4all.nl>
From:	"yeep" <yeep AT xs4all DOT nl>
To:	<opendos-developer AT mail DOT tacoma DOT net>
Subject:	Re: 32bit BIOS
Date:	Sat, 22 Mar 1997 00:29:46 +0100
MIME-Version:	1.0

> > Some guy posted something about why the bios creators (Award, AMI)
don't
> > create 32bit bioses.
> 
> > Well It just occured to me, that that's because the CPU's natural state
is
> > 16bit.
> > So first the CPU should boot up (or start or whatever) in 32bit mode,
then
> > the bios can be 32bit and we shall all be happy.
> 
> Well, not quite. If the CPU is in protected mode with a 32 bit code 
> segment, standard DOS software won't run, DOS won't run, and nothing will
> be able to boot without a custom bootloader that uses the new standard.

I was a bit vague on that, but what I meant was that if the CPU starts up
in Prot mode, you can use a 32bit OS for real!!!
 
> It's easier to have the system boot in real mode, as per standard, but
provide
> a protected mode interface in the BIOS, like the VESA folks did.
> 
> > Ofcourse....unless the bios sets the CPU in 32bit mode, before doing
> > anything else....hmmmmm...
> 
> Yes, exactly. A 32 bit protected mode OS starts in 16 bit real mode,
doesn't it?

Yes, see above.

	Yeep

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