Control unit.
D
danger (notice)
A word to call attention to possible lethal harm to people. Contrast with attention and caution.
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.
See electronic mail.
EPO
Emergency power off.
EPROM
Erasable programmable read only memory.
IBM TS22xx - TS2290, TS2280, and TS2270
75