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Can read PCI config space, but not normal space on one motherboar-d?

OSR_Community_UserOSR_Community_User Member Posts: 110,217
I have a PCI device that works fine in all of the motherboards I've tried
except for the Intel Seattle (SE440BX-2) motherboard.

When it works fine in other motherboards, I can read the PCI config space
(programatically, with PCIview, or by using the PCI command in SoftICE), and
then there are also 256 registers at a memory location that I can read. My
driver can map those registers and read them. Also, I can do a PEEKD in
SoftICE and get the expected values.

On the Intel Seattle motherboard, however, I can read the PCI config space,
but when I try to read the registers, I always read 0xFFFFFFFF. I have the
same problem when I do a PEEKD in SoftICE.

Note that the device is at least partially functional, since I can read the
PCI config space. Additionally, the same card works in other systems with
other motherboards.

I looked around for conflicts in the memory, but saw none. I also grabbed
the newest BIOS, but that didn't help.

Does anyone have any ideas what I should look at next? I'm at a loss to
explain how that could happen!

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