RE: Accessing memory in 32-bit space

["John R Pierce" <pierce@scruznet.com>]

You will need some sort of dos extender, and you will have to live within
the rules of that extender... Basically, you will need to first make the
PCI-bios
calls to locate your board and get its physical base address, then you
will need to make the dos-extender calls to map that physical address
into a logical address that you can use in your software.  The details
of this latter are quite dos-extender specific... if its a 16 bit dos
extender,
you will probably need to allocate a LDT selector, and set its base address
and limits appropriately... if its a 32bit extender, there should be some
sort
of MapPhysToLinear() call that will convert the physical address into a
linear
address.

I'm not an expert on dos extenders, so I can't help on the details...  I've
only
done this sort of thing under MS Windows and Windows/NT...

-jrp

----------
From: 	Henry Lau
Sent: 	Monday, July 29, 1996 11:25 AM
To: 	Mailing List Recipients
Subject: 	Accessing memory in 32-bit space

I am trying to develop some diagnostics routines running in DOS to
access shared memory on a PCI board.  So I need to way to read
and write memory in 32-bit PCI space after I've figured out where
the board's shared memory is mapped from the configuration registers.

Any BIOS call I can use?  Any other suggestions?

Thanks

Henry Lau
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