Re: BIOS & Pmode

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Article #310

#310

From: Cyrus W.
Date: Sat, 24 Jun 2000 00:00

19 lines
1665 bytes

As long as your protected mode segment starts at zero you can access the BIOS
data at
400h (*16 the real mode segment value + your offset), chances are though that
you have to create a new descriptor.

Cyrus W.

Beanpole wrote:

> What is the best way to access a BIOS memory location from 32 bit protected
> mode (DPMI)?
> Right now I'm switching from 32 bit pmode to 16 bit real mode, reading the
> necessary locations and returning to pmode.  This seems wasteful.  Is there
> a formula to convert a 16 bit seg:off address to a 32 bit pmode address for
> direct access or do I need to create a descriptor with its base at 40h.  I
> appreciate any accurate info.
> Thanks
> Beanpole
>

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From: "Cyrus W." <cyrus@aareus.com>
Subject: Re: BIOS & Pmode
Date: 2000/06/24
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