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Hello,
I designed a PCI target card.
A minority of wintel computers are clearing ( or
simply not setting ) the memory access enable bit of the command register.
As a result my application software fails to communicate with my PCI board's
memory.
My PCI card's BAR is successfully assigned an
address at power up. After that happens I thought that the PCI-BIOS sets the
memory access enble bit. Is this the case ? Could the OS be clearing this bit
later ? Can an application program set this bit ?
What are the rules for setting/ clearing this bit
?
Under what conditions would the OS or the
PCI-BIOS clear this bit or fail to set ths bit ?
Any advice would be much
appreciated.
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