Service manual

Interfaces
1-16 Eleventh Edition (K) 96022
StorageTek Protected
■ Interfaces
The L80 has library interfaces, drive interfaces, and user interfaces.
Library Interfaces
The library interfaces are small computer system interface (SCSI HVD and LVD) or,
with the addition of an internal or external Fibre Channel router, Fibre Channel-to-SCSI
LVD.
The following table describes issues to consider when combining devices and bus types.
In the future, Native Fibre will be available. It will:
• Allow the library to connect to Fibre Channel networks
• Increase the client server-to-library distance from 25 m (82 ft) to 500 m (1,640 ft)
• Be less expensive than a router
Drive Interfaces
The drive interfaces are SCSI high voltage differential (HVD) or SCSI low voltage
differential (LVD). The HVD interface allows longer cable lengths, but throughput is
slower than with the LVD interface. The LVD interface restricts cable lengths, but
provides faster throughput.
The following table shows the types of drives and the interfaces that are supported.
Table 1-2. SCSI Device/Bus Types: Issues
If you plug a . . . Into . . . The result is . . .
Single-ended device
Single-ended bus Proper connection
LVD bus Single-ended mode
HVD bus Operation disabled
Low voltage
differential device
Single-ended bus Single-ended mode
LVD bus Proper connection
HVD Potential damage/disabled device
High voltage
differential device
Single-ended bus Disabled device
LVD bus Potential damage/disabled device
HVD bus Proper connection