Accessing PCI memory above 1MEG

[John Moore <JohnMo@Attachmate.com>]

PCI-SIG Group,

I am a software developer writing a Window 3.1 DLL that will
access the memory of a PCI board above 1MEG.

I am reading a 32-bit memory address that exist above 1MEG 
(i.e. 0xFFFBC000) from the PCI Configuration registers, but
when I try to access this memory, either in 32-bit or by
generating a 16-bit selector (from DPMI), it will lock up my
machine. I have tried to look at this memory with various
debuggers, but the debuggers can not dereference the memory
address in 16- or 32-bit.

I have seen reference in a couple of documents that mentions
something about mapping PCI memory to CPU memory but I cannot
find out how to do this in a Win 3.1 environment.

Does anyone know how I go about accessing this upper memory
area and/or where I can go to get the answer?

John Moore
Staff Software Engineer
Attachmate Corp.
Email: JohnMo@attachmate.com

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