Sun Microsystems Netra T4 AC100, Service And System Reference Manual

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11-6 Netra T4 AC100/DC100 Service and System Reference Manual • August 2001
11.3.1 SCSI Implementation
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SCSI-3 Fast-20 (UltraSCSI) parallel interface
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16-bit SCSI bus
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40Mbps data transfer rate
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Support for 16 SCSI addresses:
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Target 0 to 6 and 8 to F for devices
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Target 7 reserved for SCSI host adapter on main logic board
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Support for up to seven internal SCSI devices (including the host adapter):
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Fast-20 SCSI disk drive target 0 (left-most drive slot)
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Fast-20 SCSI disk drive target 1
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Fast-20 SCSI disk drive target 2
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Fast-20 SCSI disk drive target 3 (right-most drive slot)
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Fast-10 SCSI removable media device target 4
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Fast-10 SCSI removable media device target 6
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Support for external 8-bit and 16-bit SCSI devices via 68-pin SCSI connector
mounted on an adapter board
11.3.2 SCSI Cabling and Configuration
The SCSI-3 Fast-20 (UltraSCSI) specification requires that the external SCSI bus
length be limited to 3m (10ft) for less than five devices (internal and external), and
1.5m (5ft) for five to eight devices. When SCSI-3 and SCSI-2 devices are connected to
the Netra T4 system SCSI bus, the system enables each device to operate at its
respective data transfer rate. The last external SCSI device in a daisy-chain must be
terminated internally (active termination) or with an external terminator according
to Forced-Perfect Termination (FPT) technology.
11.3.2.1 SCSI Cabling Procedure
1. Count the number of SCSI devices on the system SCSI bus. Be sure to count the
host adapter as a SCSI device.