Sun Microsystems TIMBERWOLF 9740 - Manual (Page 63)

95693 Revision P 4-1
4
Drives
This chapter contains an overview about the controller transport units (CTUs)
and tape drives for the 9740 Library Storage Module (LSM).
Note: See Appendix A for information about the cartridge tapes.
CTUs mount in cartridge drives that attach to the rear of the LSM. Each cartridge
drive can contain:
• Two or four 9490 (TimberLine) CTUs
• One to four SD-3 (RedWood) CTUs
Tape drives mount inside the 9741 or 9741E Drive Cabinets that attach to the
rear of the LSM. These drive cabinets can contain:
• One to ten Digital Linear Tape (DLT) drives
• One to ten T9840 Tape Drives
• One to ten T9940 Tape Drives
• A combination of DLT, T9840, or T9940 drives
Note: Only two of the three drive types that can be installed in a 9741/9741E
Drive Cabinet are allowed to be mixed in the same cabinet.
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Controller Transport Units
Controller transport units (CTUs) are independent subassemblies within the cartridge
drive. Each CTU consists of a separate controller and transport and provides a 1-by-1
architecture. Because of this 1-by-1 architecture:
• Operation of one CTU does not effect the operations of any other CTUs in
the cartridge subsystem.
• Maintenance on a CTU does not disrupt operations of any other CTUs in the
cartridge drive or cartridge subsystem.
The controller contains all the circuit cards required for operation, such as: the
interface card, read and write cards, and microprocessors.
The transport contains the electrical, mechanical, and pneumatic components
required for tape motion, read and write operations, loading and unloading of
the cartridge tape.
There are two types of CTUs that attach to the LSM: 9490 and SD-3.