LaCie DDS4 Drive, Руководство пользователя

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Warning! Your LaCie drive is not compatible with HVD devices or
buses! Never connect your LaCie drive to an HVD bus or peripheral.
Doing so may damage your drive and/or system, and will void your
warranty.
LVD (Low Voltage Differential) – This latest addition to the SCSI interface,
which became important with Ultra2 SCSI, combines all of the advantages of
SE and HVD. LVD has rapidly become the de facto standard in high-
performance SCSI. Its benefits include increasingly lower cost, more and more
widespread use, enhanced reliability, higher data transfer rates, compatibility
with the newest high-speed hard drives, longer cable lengths than SE (up to
12 m), and backwards compatibility with older SCSI technologies.
The following table shows the different types of SCSI implementations:
Category Narrow (8
bit)
Wide (16
bit)
Wide (16
bit)
Wide (16
bit)
Wide (16 bit)
SCSI types Fast SCSI Ultra
Wide SE
Ultra2
Wide
(LVD)
Ultra 160
(LVD)
Ultra 320 (LVD)
Transfer rate 10MB/s max 40MB/s
max
80MB/s
max 160MB/s
max 320MB/s max
# of devices 8 max 16 max 16 max 16 max 16 max
Cable length 3 m max 1.5 m max 12 m max 12 m max 12 m max
Connectors 25 or 50-pin 68-pin 68-pin 68-pin 68-pin
Fundamental SCSI rules
Follow these seven basic rules when setting up your SCSI peripheral or chain.
1) Give each SCSI peripheral a unique ID number.
Each device in your SCSI chain needs a unique ID number, either from 0 to 6
for Narrow SCSI, or any number between 0-6 and 8-15 for Wide SCSI (ID 7 is
generally reserved for your computer’s SCSI controller). No two devices in the
same chain may have the same ID number, but the order in which the devices
are connected in the bus does not matter. For example, the device with ID 2
could be physically located at the end of the chain, while the device with ID 6
is connected directly to the SCSI port of your computer.
2) Always terminate your SCSI chain.
The last device in your SCSI chain must be terminated. Even if you have only
one SCSI peripheral in your chain, you must terminate it. Single-ended SCSI
devices may have an internal terminator (using an on/off switch) or may
require an external terminator.