Sony DDS-4, Руководство по описанию продукции

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8 - 8 SONY SDT-10000/SDT-11000 DDS Tape Drive
APPENDIX D - GLOSSARY
Fault Log
The Fault Log is stored in RAM in the SDT-10000/SDT-11000 and holds a record of Self-
Test failures and all problems which have been met during normal operation.
Frame Two adjacent tracks, one A channel and one B channel.
Filemark
A mark written by the host. It does not necessarily separate files. It is up to
the host to assign a meaning to the mark. Consist of a special recorded
element within a partition, containing no user data, which provides a
segmentation scheme.
Group A fixed capacity set of frames written onto or read from the tape. A group contains one index
and can contain several records, partial records, Filemarks and Setmarks.
Hard Error
A Hard Error is an uncorrectable data error. During writing, this is defined
as being uncorrected after the RAW retry limit has been exceeded. During reading, a hard
error is logged if a group is uncorrectable by C1, C2 or C3 ECC.
Head clog
Particles from the tape or from outside the drive adhere to the head gap on a
read or write head and obstruct the reading or writing of data. The particles will become
dislodged by the operation of the internal head cleaner and/or
cleaning tape.
Index Information stored at the end of a group which specifies the contents of the
group. Every group except the Vendor Group contains an index.
Lead-in Area
The first section of the tape used for loading, BOT positioning, and tape
usage logging.
Load To insert a cassette into the drive. The drive automatically threads the tape
and goes online.
LUN Logical Unit Number, by which a device is identified on the SCSI bus. The
Sony SDT-10000/SDT-11000 has an LUN of 0 fixed in the firmware.
Noise Any kind of magnetic or electric interference detected by the electronics.