Pci Boxes; Sample I/O Subsystem - Compaq AlphaServer 160 User Manual

3.8

PCI Boxes

A QBB supports up to two PCI boxes. A cable connects the QBB "local"
I/O riser to the "remote" I/O riser in the PCI box. There are two I/O
ports on a local I/O riser.
remote I/O riser. Figure 3–10 shows QBB0 connected to PCI box 0 and
PCI box 1.
Figure 3–10 Sample I/O Subsystem
PCI Box 0
PCA
Chip
PCI Bus
PCI Bus
PCI Bus
Remote I/O
Riser 1
1
Local I/O Riser
3-18
AlphaServer GS80/160/320 User's Guide
Each I/O port is used to connect to one
PCI Box 1
PCI Bus
PCA
Chip
PCI Bus
Remote I/O
Riser 0
0
QBB0
PCA
Chip
PCI Bus
PCA
Chip
PCI Bus PCI Bus
Remote I/O Remote I/O
Riser 1 Riser 0
3 2
Local I/O Riser
PK-0652-99