February, 2007
Configuration Header Registers
Register 11-7. 18h Bus Number (All Ports)
Serial
EEPROM
Bit(s)
Description
Type
Default
Primary Bus Number
7:0
RW
Yes
00h
Records the Bus Number of the PCI Bus segment to which the primary
interface of this port is connected. Set by Configuration software.
Secondary Bus Number
15:8
RW
Yes
00h
Records the Bus Number of the PCI Bus segment that is the secondary
interface of this port. Set by Configuration software.
Subordinate Bus Number
23:16
31:24
RW
RO
Yes
No
00h
00h
Records the Bus Number of the highest numbered PCI Bus segment that
is subordinate to this port. Set by Configuration software.
Secondary Latency Timer
Cleared to 00h, as required by the PCI Express Base r1.0a.
ExpressLane PEX 8532AA/BA/BB/BC 8-Port/32-Lane Versatile PCI Express Switch Data Book
Copyright © 2007 by PLX Technology, Inc. All Rights Reserved – Version 1.6
159
PLX [ PLX TECHNOLOGY ]
