14 Installing the Cross-Connect Panel
Practice 450-1011-201
(3) Push one end of the SCSI cable onto the 50-pin connector at the upper left of
the rear panel of the Primary Processor or the File Processor, as viewed from
the rear. The connector is keyed so that it connects only one way.
(4) Tighten the two screws on the connector with a flat-blade screwdriver.
(5) If a Mass Storage SRU has a thumbwheel on the rear panel, set the thumbwheel
setting to the SRU's address on the SCSI bus. (Addresses 0, 2, 3, and 4 on the
SCSI bus are reserved for disk storage SRUs. The first disk storage SRU in the
cluster has address 0. Addresses 2, 3, and 4 are assigned in that order as
additional disk storage SRUs are added to the SCSI cluster.)
Note: Some Mass Storage SRUs do not have thumbwheels. Instead they have
address indicators on the rear panels, with + and - buttons. For an SRUof this
type, use the buttons to set the address after the system has been powered up.
(6) Push the other end of the cable onto the left-most (as viewed from the rear)
50-pin connector on the rear panel of the Mass Storage SRU. The connector is
keyed so that it connects only one way.
(7) Locate the appropriate length of SCSI cable for the Cartridge Tape SRU
connection.
(8) Push one end of the SCSI cable onto the second 50-pin connector at the rear of
the Mass Storage SRU. The connector is keyed so that it connects only one way.
(9) Tighten the two screws on the connector with a flat-blade screwdriver.
(10) Route the cable to the Cartridge Tape SRU. Dress the cable as necessary.
(11) Push the free end of the cable onto the 50-pin SCSI connector on the rear of
the Cartridge Tape SRU. The connector is keyed so that it connects only one
way.
Note: If connecting to a Nine-track Magnetic Tape Unit, the unit must be the
last physical unit on the SCSI bus and must be located no more than 5.5 m (18
ft) from the SRU in the cabinet to which it connects. The SCSI cable can be
connected to either of the SCSI connectors inside the tape unit. (Refer to the
manufacturer's documentation for further information.)
(12) Make the other SCSI cable connections similarly, dressing the cables as
required.
(13) Tape SRUs and 1/4 Shelf Disk/Tape SRUs have DIP switches that must be set
to indicate the address on the SCSI bus. Set or verify the settings of the switches
on each such SRU. The switches are on the front of the 1/4 Shelf Disk/Tape
SRU, and on the rear of other SRUs that have cartridge tape drives. Beside the
switches there is a diagram showing how to set them for each possible address
on the bus. The 1/4 Shelf Disk/Tape SRU must have one of the addresses
reserved for disk storage SRUs (0, 2, 3, and 4). Addresses 1 and 5 on the bus are
reserved for the first and second tape devices in the SCSI cluster.
(14) Install the bus terminator on the unused connector on the last device on the
SCSI bus.
