Scsi Bus Physical Description; Characteristics - Sun Microsystems storagetek sl500 Reference Manual

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C H A P T E R

SCSI Bus Physical Description

This chapter contains the physical description for the small computer system
interface (SCSI) bus for the SL500 library, including:

Characteristics

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Interface cables
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Special signals
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P-cable to A-cable adapters
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Characteristics
The library supports single-ended/LVD (low-voltage differential) for the SCSI bus
connection. The following paragraphs describe the characteristics for these
alternatives.
The single-ended alternative has the following characteristics:
Maximum cable length of 3 m (9.8 ft)
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Minimum cable length of 0.3 m (1 ft)
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Primarily for connections within a cabinet
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0.1 m (4 in.) stubs (the distance from the on-board device to the bus)
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Twisted-pairs cables (sometimes)
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Less power than the differential alternative
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Low cost
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Lower performance data rates than LVD
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The LVD alternative has the following characteristics:
Maximum cable length of 12 m (39.4 ft)
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Minimum cable length of 0.36 m (14.2 in.)
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0.1 m (4 in.) stubs (the distance from the on-board device to the bus)
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Usable for outside cabinet connections
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LVD- or Universal-rated cables
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96122 • Revision: F 7