Seagate Elite 9, Руководство по эксплуатации продукта

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58 Elite 9 Product Manual, Rev. C
Wide I/O
Connector
ST410800WD
I/O Terminating
Resistors
Non-wide I/O
Connector
ST410800ND
I/O Terminating
Resistors
Figure 19. Terminating resistor locations for ND and WD drives
Notes:
[1] Positive logic enables transmitter (
+
5V = asserted).
Negative logic enables receivers (0V = asserted).
[2] Negative logic signal (0V = asserted).
[3] Total interface cable length should not exceed 82 feet (25 meters) from
the host to the end of the daisy chain.
[4] You must provide terminators.
11.7.3.3 Terminator requirements
ST410800N/W drives. Internal disc drive I/O termination consists of active
circuits in permanently mounted IC terminator packs on the main PCB. All
single initiator/single target (non-daisy-chain) applications require you to
terminate the initiator and drive. Daisy-chain configurations require you to
terminate only the units at each end of the daisy chain. Do not terminate any
other peripheral on the chain. All terminators in the daisychain must be ANSI
SCSI-2 Standard’s alternative 2 terminators (active terminators).
Note. Remove the Terminator Enable jumper from J4A pins 19 and 20
when terminators are not required.
ST410800ND/WD drives. Differential drives are shipped with terminators
installed in sockets next to the I/O connector on the circuit board. See Figure
19. All single initiator-single target (non-daisy-chain) applications require you
to terminate the initiator and drive. Daisy-chain configurations require you to
terminate only the units at each end of the daisy chain. Do not terminate any
other peripheral on the chain.
Note. Remove the terminators from their sockets when terminators are not
required.
To terminate the drive internally, install terminating resistors (part number
15479501) in these sockets.