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Re: Can read PCI config space, but not normal space on one motherboard?

OSR_Community_UserOSR_Community_User Member Posts: 110,217
Are you sure that the physical memory is assigned to the same region. Is
that runtime space pointed by BAR0 or BAR1?

Alternatively, is it also available in I/O space? You can recognize it when
the lowest bit of address of BAR0 or BAR1 is set. PCIview shows it.

BAR0 and BAR1 are located at locations 0x10 and 0x14 in the config space.


George Blat

At 02:51 PM 5/5/00 -0700, you wrote:
>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!
>You are currently subscribed to ntdev as: [email protected]
>To unsubscribe send a blank email to $subst('Email.Unsub')
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