From: Adam Majer <ummajera AT cc DOT UManitoba DOT CA>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: DPMI GPF problem
Date: Mon, 15 May 2000 18:36:09 -0500
Organization: The University of Manitoba
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On Sun, 14 May 2000, Malcolm Herring wrote:

> I need to map to a physical address range to access a memory-mapped device.
> The following code fragments is how I have tried to do it, but this results
> in a GPF when 'movedatal' is called.

To map physical memory (like DMA) you need to use VDS (Virtual DMA
Specifications). They are found on MS site. They are supported by most
DPMI servers.

If you want to access video memory, you need to get the memory mapping
first. You cannot simply translate it yourself as in real mode since
paging is usually on.

    Sincerely,
    Adam