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Re: PCI Signal Loading



Hi Scott,

I don't understand exactly which is the errata you are talking about. I used S5933QB in the bus master
mode, asserting and deasserting it's bus master enable pins from the add-on side. I was first afraid that
according to the errata, the last retried long word from the FIFO(currently in holding register) would get
lost during a data transfer from the add-on side to the PCI bus in 5933. This could happen only if we use
the add-on to PCI FIFO empty signal to indicate to the add-on side hardware to deassert the bus master
enable signal. But in my case the add-on side 25MHz uP responded quite slow(interrupt driven and hence
kernel dependent too!!)  to deassert the bus master enable signal, any retry would have got finished by
that time. So I didn't face a problem during the last dword retries! So it all depends on the speed of the
add-on side hardware. I feel that this is because, according to the PCI Specs., the retry should get
completed with in 16 clock cycles. But your problem could be different so I don't know whether this was of any help.

regards

-Jasper
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*  Jasper Balraj                                                      *
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