Glossary
106 Quantum LTO-7 HH SAS User’s Guide
cleaning cartridge A tape cartridge that is used to clean the heads of
a tape drive. Contrast with data cartridge.
command A control signal that initiates an action or the start of a
seque
nce of actions.
compact disc (CD) A disc, usually 4.75 inches in diameter, from which
data is read opticall
y by means of a laser.
compression The process of eliminating gaps, empty fields,
redundancies, and u
nnecessary data to shorten the length of
records or blocks.
concurrent Refers to diagnostic procedures that can be run on one
control uni
t while the rest of the subsystem remains available
for customer applications.
contingent connection A connection between a channel path and a
drive caused when
a unit check occurs during an I/O operation.
controller A device that provides the interface between a system and
one or more
tape drives.
CP Circuit protector.
ctrl Control.
CU 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 m
eaning 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 cl
eaning cartridge.
data check A synchronous or asynchronous indi
cation of a condition
caused by invalid data or incorrect positioning of data.
dc Direct current.
To Next Page
Loading...
