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Re: Non PCI bursting cards should go to the trash can

Jawad Qureshi <qureshi_jawad@usa.net> écrit :
[...]
> I am facing some problems with the pci. I have two questions about Pci.
> First is that 
> 1-how one can explicitly specify to brust on the pci device;
> 2-We have a custom made pci card . The problem is that the transfer on this
> card is slow. I am making 40 double word transfers from the fifoes on the
> board to the memory. The pci card does not allow brusts. These transfers are
> taking almost 32us. Can any body tell why this much time is taking place.

32us/40 = 800ns. PCI at 33MHz, cycle = 33ns -> 24 cycle/access.
The *address* phase of a PCI r/w cycle eats 6 cycles for himself at least.
It looks rather normal.

-- 
Ueimor
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