IBM x 340 Series, Hardware Maintenance Manual

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Hardware Maintenance Manual: xSeries 340 Model 6RY
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 15. 68-pin SCSI connector pin-number assignments.
Pin Signal Pin Signal
1 +Data 12 35 -Data 12
2 +Data 13 36 -Data 13
3 +Data 14 37 -Data 14
4 +Data 15 38 -Data 15
5 +Data P1 39 -Data P1
6 +Data 0 40 -Data 0
7 +Data1 41 -Data 1
8 +Data 2 42 -Data 2
9 +Data 3 43 -Data 3
10 +Data 4 44 -Data 4
11 +Data 5 45 -Data 5
12 +Data 6 46 -Data 6
13 +Data 7 47 -Data 7
14 +Data P 48 -Data P
15 Ground 49 Ground
16 DIFFSENS 50 Ground
17 Term power 51 Term power
18 Term power 52 Term power
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