Chapter 2. Installing the Library
16
LVD/SE SCSI Bus
The LVD/SE library operates in either single-ended or low-voltage-differential SCSI
mode, depending on the type of bus that is attached.
Note: The entire bus (including host bus adapter, devices, and
termination) must be LVD to operate in LVD mode. Attaching any
single-ended SCSI device to an LVD bus renders the entire bus
(and all attached devices) subject to the maximum specification
requirements for single-ended SCSI (including maximum cable
lengths).
The LVD/SE terminator should function in either mode. To check the mode in which
your library is operating, look at the library terminator and the terminator’s light-
emitting diode (LED). The top of the terminator lists the color of the LED for each
mode.
SCSI specifications for LVD and single-ended modes are shown in this table:
Attaching the SCSI Cable
Note: The library requires a minimum of two SCSI IDs on the SCSI bus.
To attach the library to the host computer:
1. Turn off the computer and library.
2. Determine the correct specifications for the SCSI cable as described in SCSI
Cable Requirements on page 79.
3. Attach the SCSI cable to the connector on the back of the library.
4. Attach the other end of the SCSI cable to the host computer.
SCSI Specifications LVD Mode Single-Ended Mode
SCSI Bus Width 16 bits 16 bits
Maximum Bus Speed 80 MB/sec 40 MB/sec
Maximum Bus Cable Lengths 12 metersa1.5 metersa
aMaximum cable length requirements include the internal cabling for each device. The library contains 60 centimeters (24 inches) of
cabling inside the library.