IBM TS2280, Руководство по установке, эксплуатации и обслуживанию

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data Any representations such as characters or
analog quantities to which meaning is or
might be assigned.
data buffer
The storage buffer in the control unit.
This buffer is used to increase the data
transfer rate between the control unit and
the channel.
data cartridge
A tape cartridge that is dedicated to
storing data. Contrast with cleaning
cartridge.
data check
A synchronous or asynchronous
indication of a condition that is caused by
invalid data or incorrect positioning of
data.
dc Direct current.
degauss
To make a magnetic tape nonmagnetic by
using electrical coils that carry currents
that neutralize the magnetism of the tape.
degausser
A device that makes magnetic tape
nonmagnetic.
degradation
A decrease in quality of output or
throughput or an increase in machine
error rate.
degraded
Decreased in quality of output or
throughput or increased machine error
rate.
deserialize
To change from serial-by-bit to
parallel-by-byte.
detented
A part that is held in position with a
catch or lever.
device Any hardware component or peripheral
device, such as a tape drive or tape
library, that can receive and send data.
device driver
A file that contains the code that is
needed to use an attached device.
DIAG
Diagnostic section of maintenance
information manual.
differential
See High Voltage Differential (HVD).
direct access storage
A storage device in which the access time
is independent of the location of the data.
DNS Directory Name System. This system
allows the library to recognize text-based
addresses instead of numeric IP
addresses.
download
To transfer programs or data from a
computer to a connected device, typically
a personal computer.
To transfer data from a computer to a
connected device, such as a workstation
or microcomputer.
DRAM
Dynamic random-access memory.
drive, magnetic tape
A mechanism for moving magnetic tape
and controlling its movement.
DRV Drive.
DSE Data security erase.
DSP Digital signal processor.
E
EBCDIC
Extended binary-coded decimal
interchange code.
EC Edge connector. Engineering change.
ECC Error correction code.
EEPROM
Electrically erasable programmable
read-only memory.
EIA Electronics Industries Association.
EIA unit
A unit of measure, which is established
by the Electronic Industries Association,
equal to 44.45 millimeters (1.75 inches).
eject To remove or force out from within.
electronic mail
Correspondence in the form of messages
that are transmitted between user
terminals over a computer network.
email See electronic mail.
EPO Emergency power off.
Glossary
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