IBM 86655RY Hardware Maintenance Manual - Page 96

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 the 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. 34 1 68 35 Table 14. 68-pin SCSI connector pin-number assignments. Pin Signal Pin 1 +Data 12 35 2 +Data 13 36 3 +Data 14 37 4 +Data 15 38 5 +Data P1 39 6 +Data 0 40 7 +Data1 41 8 +Data 2 42 9 +Data 3 43 10 +Data 4 44 11 +Data 5 45 12 +Data 6 46 13 +Data 7 47 14 +Data P 48 15 Ground 49 -Data 12 -Data 13 -Data 14 -Data 15 -Data P1 -Data 0 -Data 1 -Data 2 -Data 3 -Data 4 -Data 5 -Data 6 -Data 7 -Data P Ground Signal 86 Hardware Maintenance Manual: Netfinity 7600 - Type 8665 Models 1RY, 2RY