Date: Wed, 5 Jun 1996 17:39:41 +0200 (IST)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
To: Bryanston School <MOLESWORTH DOT THOMAS AT bryanston DOT co DOT uk>
Cc: DJGPP <djgpp AT delorie DOT com>
Subject: Re: Accessing physical memory
In-Reply-To: <000000246612916820372@bryanston.co.uk>
Message-Id: <Pine.SUN.3.91.960605173642.26657G-100000@is>
Mime-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII


On Wed, 5 Jun 1996, Bryanston School wrote:

> The memory used here is physical, PC, memory, that's an area
> in the 32Mb of memory that I have. The board itself doesn't have
> any memory on it. What I want to do is to allocate an area of
> memory, find out the exact address and size, and tell the board
> where to put it (it uses PCI DMA transfers or something, not sure
> exactly how it works). The way I've been doing it so far is to

AFAIK, this is only possible with DPMI servers that support DPMI v1.0 
spec.  It is also possible that you can use the Virtual DMA Services API 
(invoked with Int 4Bh, see the Interrupt List), but this requires that 
you run under a memory manager that supports it, such as QEMM.