Maxtor DIAMONDMAX 91536H2 - Manual (Page 63)

GLOSSARY
GL – 6
SOFT ERROR
A data error which can be overcome by rereading the data or
repositioning the head.
SOFT SECTORED
A technique where the controller determines the beginning of a
sector by the reading of format information from the disk. This is
contrasted to hard sectoring where a digital signal indicates the
beginning of a sector on a track.
SOFTWARE
Applications programs, operating systems, and other programs (as
opposed to hardware).
SPINDLE
The rotating hub structure to which the disks are attached.
SPINDLE MOTOR
The motor that rotates the spindle and therefore the disks.
SPUTTERED MEDIA
Magnetic disk or tape that has the magnetic layer deposited by
sputtering means.
STEPPER MOTOR
A motor that has known detent positions where the rotor will stop
with the proper control in some cases. The digitally controlled motor
moves the head positioner from track to track in small, step-like
motions.
STORAGE CAPACITY
The amount of data that can be stored in a memory location, usually
specified in kilobytes for main memory and floppy drives and
megabytes for mass storage devices.
STORAGE DENSITY
Usually refers to recording density (BPI, TPI, or a combination of the
two.)
STORAGE LOCATION
A memory location, identified by an address where information may
be read or written.
STROBE OFFSET SIGNAL
A group of digital input signal levels which cause the read PLL and/
or data decoder to shift the decoding windows by fractional
amounts. Often early/late are modified when two signals are used.
T
THIN-FILM HEAD
A magnetic transducer manufactured by deposition of magnetic and
electrical materials on a base material contrasted with prior art
mechanical methods. Read/write heads whose read/write element is
deposited using integrated circuit techniques rather than being
manually wound.
THIN-FILM MEDIA
See plated thin film media.
TRACK
One surface of a cylinder. A path which contains reproducible
information left on a magnetic medium by recording means
energized from a single channel.
TRACK-FOLLOWING SERVO
A closed-loop positioner control system that continuously corrects
the position of the disk drive’s heads by utilizing a reference track
and a feedback loop in the head positioning system. (See also
closed loop.)
TRACKS PER INCH (TPI)
A measurement of radial density. Tracks per inch of disk radius.
TRACK POSITIONING
The method, both mechanical and electrical, used to position the
heads over the correct cylinder in a disk drive system.
U
UN-CORRECTABLE ERROR
An error that is not able to be overcome with Error Detection and
Correction.
UNFORMATTED CAPACITY
Storage capacity of disk drive prior to formatting; also called the
gross capacity. (See format.) The raw capacity of a drive not taking
into account the capacity loss due to storage of the format control
information on the disk surfaces.
UNRECOVERABLE ERROR
A read error falling outside the capability of an ECC mechanism to
correct, or not able to be overcome by rereading the data in
question, with or without repositioning the head.
V
VOICE COIL MOTOR
A positioning motor that uses the same principle as a voice coil in a
loudspeaker. The motor has no detent positions. The mechanical
motion output of it can be either rotary or linear.
W
WHITNEY HEAD
A successor to the original Winchester read/write head design. The
primary change was to make the flexure smaller and more rigid. First
used in IBM 3370/3380.
WHITNEY TECHNOLOGY
A method of constructing a read/write head in a rigid disk drive
using a Whitney head. In all other details it is the same as
Winchester technology.
WINCHESTER HEAD
The read/write head used in Winchester technology, non-removable
media disk drives. May be either a monolithic or composite type. It is
aerodynamically designed to fly within microinches of the disk
surface.
WINCHESTER TECHNOLOGY
A method of constructing a rigid disk drive using concepts
introduced in the IBM model 3340 disk drive. The primary changes
from prior technology was to lower the mass of the slider, use of a
monolithic slider, radically changing the design of the flexure and
having the slider come to rest on a lubricated disk surface when disk
rotation ceases. In addition to the above, a totally sealed chamber
containing the read/write heads and disks was used to protect
against contamination.
WINDOW MARGIN
The amount of tolerance a read/write system has for transition jitter
at a specified error rate level.
WORD
A number of bits, typically a multiple of eight, processed in parallel
(in a single operation). Standard word lengths are 8, 16, 32 and 64
bits (1, 2, 4, or 8 bytes).
WRITE
The recording of flux reversals on a magnetic media.
WRITE PRE-COMPENSATION
The intentional time shifting of write data to offset the effects of bit
shift in magnetic recording.
WRITE GATE SIGNAL
A digital input signal level which causes the drive circuitry to record
(write) data.