HP A3716A DDS-3 Autoloader User's Manual - 3716-96001

Glossary-1
Glossary
ANSI
American National Standards Institute, which sets standards for SCSI and
the safety of electrical devices, amongst other things.
ATF
Automatic Track Followinga method of ensuring the head is in the center
of the track being read, used in HPs DDS-1 and DDS-2 drives.
autoload
When a tape cartridge is inserted, a tape drive with autoload will
automatically load it, without the host having to send a load command. If a
drive does not have autoload, the drive will take no action until it receives
a load command.
autoloader
A device embodying a tape drive and a cartridge changer mechanism,
housed in a single case.
BIOS
Basic Input/Output System. Software coded into chips. A host adapter, for
example, may have a BIOS, which can be enabled or disabled.
bit error rate
BOD
Beginning of Data. The start of recorded data in a partition on a tape.
BOM
Beginning of Media. The first point on the tape that can be accessed by the
drive.
BOP
Beginning of Partition. The position at the beginning of the permissible
recording region of a partition.
changer mechanism
A mechanism within an autoloader for moving tape cartridges from the
magazine into the tape drive and back again.
See also random mode, stacker mode
changer mode
Another name for random mode.
compression
A procedure in which data is transformed by the removal of redundant
information in order to reduce the number of bits required to represent the
data.
compression ratio
A measure of how much compression has occurred, defined as the ratio of
the amount of uncompressed data to the amount of compressed data into
which it is transformed. The DCLZ algorithm used to compress data in HP
DAT drives can typically achieve a compression ratio of between 2:1 and 4:1
depending on the nature of the data.
DAT
Digital Audio Tape is a helical scan recording technique for audio recording.
It uses 3.81 mm wide tape stored in a cartridge measuring 73 x 54 x 10.5 mm.
Number of errors
Number of bits written or read
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