Subsystem Positioning And Cabling; Spcn Cabling - IBM pSeries 630 6C4 Service Manual

1 Operator Panel
2 SCSI Media Device (50-pin)
3 SCSI Media Device (68-pin)
4 SCSI Media Device (68-pin)
5 CEC Backplane to Operator Panel Signal Cable
6 SCSI Media (68-pin) to 50-pin Converter Cable
7 SCSI Media Device Signal Cable to Integrated Single-Ended SCSI Connector on the PCI Riser Card
8 CEC Backplane Connector to Diskette Drive Signal Cable
9 CEC Backplane to IDE CD-ROM Signal Cable
10 Diskette Drive
11 IDE CD-ROM
12 Disk Drive Backplane
13 PCI Riser Card to Disk Drive Backplane Signal Cable
14 PCI Riser Card to Disk Drive Backplane Signal Cable
15 6-Slotted PCI Riser Card
15a 4-Slotted PCI Riser Card (Used on 4-slotted models only)
16 CEC Backplane
17 PCI Riser Card to External SCSI Signal Cable
18 External SCSI Port
19 CEC Backplane to Rack Indicator Signal Cable
20 Rack Indicator Port
21 CEC Backplane to Debug Port Signal Cable
22 Debug Parallel Port

Subsystem Positioning and Cabling

The I/O subsystem drawer can be installed in a standard 19-inch EIA rack in any location near to the
system. The cables that connect the drawers allow some flexibility in drawer placement, but the I/O
drawers should be located as close to the system unit as possible.
The Model 6C4 can have a total of two I/O drawers connected. Each drawer is connected to the system
unit using a system power control network (SPCN) cable loop and a remote I/O (RIO) cable loop.
Although the SPCN cables are connected in a loop, only one loop is needed for both of the I/O drawers.

SPCN Cabling

I/O drawer SPCN cables are connected to the system using a loop configuration. The SPCN cables are
connected in a loop so that the system has two paths to each I/O drawer. The Model 6C4 can have a total
of two I/O drawers connected in one SPCN loop.
The location codes for the I/O drawers are assigned during the system power-on sequence. Each drawer's
location is determined by its position in the SPCN loop. The first drawer in the SPCN loop (the drawer
connected to SPCN 0) is given the location U0.2. If there is a second I/O drawer in the SPCN loop, it is
assigned the location U0.3. The I/O drawers are numbered sequentially until the end of the loop is
reached at SPCN 1. For cabling examples, see the following illustrations.
Chapter 1. Reference Information
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