IBM xSeries 230 6RY Hardware Maintenance Manual page 87

SCSI cabling requirements
If you plan to attach external SCSI devices, you must order additional SCSI cables.
To select and order the correct cables for use with external devices, contact your
IBM reseller or IBM marketing representative.
For information about the maximum length of SCSI cable between the terminated
ends of the cable, refer to the ANSI SCSI standards. Adhering to these standards
will help ensure that your server operates properly.
Setting SCSI IDs
Each SCSI device connected to a SCSI controller must have a unique SCSI ID. This
ID enables the SCSI controller to identify the device and ensure that different
devices on the same SCSI channel do not attempt to transfer data simultaneously.
SCSI devices that are connected to different SCSI channels can have duplicate SCSI
IDs.
The hot-swap-drive backplane controls the SCSI IDs for the internal hot-swap
drive bays. However, when you attach SCSI devices to the external SCSI connector,
you must set a unique ID for the device. Refer to the information that is provided
with the device for instructions to set its SCSI ID.
SCSI connector pin-number assignments
The following table shows the pin-number assignments for the 68-pin SCSI
connectors.
Table 17. 68-pin SCSI connector pin-number assignments
Pin Signal
1 +Data 12
2 +Data 13
3 +Data 14
4 +Data 15
5 +Data P1
6 +Data 0
7 +Data1
8 +Data 2
9 +Data 3
10 +Data 4
11 +Data 5
12 +Data 6
13 +Data 7
14 +Data P
15 Ground
16 DIFFSENS
17 Term power
18 Term power
34
68
Pin Signal
35 -Data 12
36 -Data 13
37 -Data 14
38 -Data 15
39 -Data P1
40 -Data 0
41 -Data 1
42 -Data 2
43 -Data 3
44 -Data 4
45 -Data 5
46 -Data 6
47 -Data 7
48 -Data P
49 Ground
50 Ground
51 Term power
52 Term power
1
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Installing options
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