IBM H5S, Setup, Operator, And Service Manual

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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 dedicated to storing data. Contrast with cleaning cartridge .
data check
A synchronous or asynchronous indication of a condition caused by invalid
data or incorrect positioning of data.
dc
Direct current.
degauss
To make a magnetic tape nonmagnetic by means of electrical coils carrying
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 being held in position with a catch or lever.
device Any hardware component or peripheral, such as a tape drive or tape
library, that can receive and send data.
device driver
A file that contains the code 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 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.
G-4
TS2250 Tape Drive Setup, Operator and Service manual