Maxtor D540X-4G, Product Manual

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Maxtor D540X-4G G-1
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A
ACCESS – (v) Read, write, or update
information on some storage medium, such as
a disk. (n) One of these operations.
ACCESS TIME – The interval between the
time a request for data is made by the system
and the time the data is available from the
drive. Access time includes the actual seek
time, rotational latency, and command
processing overhead time. See also seek,
rotational latency, and overhead.
ACTUATOR – Also known as the positioner.
The internal mechanism that moves the
read/write head to the proper track. The
Maxtor actuator consists of a rotary voice coil
and the head mounting arms. One end of each
head mounting arm attaches to the rotor with
the read/write heads attached at the opposite
end of each arm. As current is applied to the
rotor, it rotates, positioning the heads over the
desired cylinder on the media.
AIRLOCK – A patented Maxtor feature that
ensures durable and reliable data storage.
Upon removal of power from the drive for
any reason, the read/write heads
automatically park and lock in a non data area
called the landing zone. AIRLOCK allows
the drive to withstand high levels of
non-operating shock. When power is applied
to the drive, airflow created from the spinning
disks causes the AIRLOCK arm to swing
back and unlock the actuator, allowing the
heads to move from the landing zone. Upon
power down, the AIRLOCK swings back to
the locked position, locking the heads in the
landing zone. A park utility is not required to
park the heads on drives equipped with
AIRLOCK (all Maxtor drives).
ALLOCATION – The process of assigning
particular areas of the disk to particular files.
See also allocation unit.
ALLOCATION UNIT – An allocation
unit, also known as a cluster, is a group of
sectors on the disk that can be reserved for the
use of a particular file.
AVERAGE SEEK TIME – The average
time it takes for the read/write head to move
to a specific location. To compute the average
seek time, you divide the time it takes to
complete a large number of random seeks all
over the disk by the number of seeks
performed.
B
BACKUP – A copy of a file, directory, or
volume on a separate storage device from the
original, for the purpose of retrieval in case the
original is accidentally erased, damaged, or
destroyed.
BAD BLOCK – A block (usually the size of
a sector) that cannot reliably hold data because
of a media flaw or damaged format markings.
BAD TRACK TABLE – A label affixed to
the casing of a hard disk drive that tells which
tracks are flawed and cannot hold data. The
listing is typed into the low-level formatting
program when the drive is being installed.
Because Maxtor disk drive’s
defect-management scheme handles all such
flaws automatically, there is no need to
concern yourself with bad track tables.
BIT – Abbreviation for binary digit. A binary
digit may have one of two values—1 or 0.
This contrasts with a decimal digit, which
may have a value from 0 to 9. A bit is one of
the logic 1or logic 0 binary settings that make
up a byte of data. See also byte.