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64-bit PCI card



Hi,

>From the PCI spec v2.1, it states that the central resource must control
the the state of REQ64# to inform 64-bit PCI cards that it is connected to
a 64-bit bus or not.  (section 3.10 pg. 108)

 "If REQ64# is deasserted when RST# is deasserted, the device is not 
  connected to a 64-bit bus.  If REQ64# is asserted when RST# is deasserted,
  the device is connected to a 64-bit bus."

My question is that for a 64-bit PCI card detecting it is NOT on a 64-bit bus
(ie. 32-bit bus) does the card terminates the upper AD[63:32], CBE[7:4] lines 
using REQ64# as the data and the RST# as the gate of a transparent latch to
control some active pullup device??? (not clear from the spec!!)

If not, how does the card terminates the upper 64-bit extension bus pins??

thanks in advance
-- 
Sincerely,
	Ray Chow
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