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HP Q153090901 User Manual

Page 188

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Glossary

188

ECMA

European Computer Manufacturers Association. The European equivalent of

ANSI.

enhanced commands SCSI commands that are vendor-unique and not part of the common SCSI set.

EOD

End Of Data. An area that signifies the end of the valid data. If new data is

written over a larger quantity of old data, it is possible for data to exist after EOD,

but because it is after EOD, this old data is no longer valid.

EOM

End Of Media format. The last usable point on the tape.

EW-EOM

Early Warning End Of Media. A physical mark or a device-computed position on

the tape that tells the drive that it is approaching EOM.

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.

filemark count

The number of filemarks written since the beginning of the current tape up to and

including the current group.

FRU

Field Replaceable Unit, an assembly or group of components that is replaced in its

entirety by Service Engineers when it contains a fault.

host

The host computer system acting as controller for the drive.

immediate mode

A mode of responding to SCSI commands where the drive or other peripheral

does not wait until the command has finished before returning status information

back to the host. For writing filemarks, Immediate mode can significantly improve

the performance of systems that do not set the Immediate bit when sending a SCSI

Write Filemarks command. On the other hand, data is not flushed to tape in

response to a filemark command.

load

The process in which the drive takes in an inserted cartridge and goes online.

LUN

Logical Unit Number, by which different devices at a particular SCSI ID can be

addressed individually. The drive has a fixed LUN of 0.

LVD

Low-Voltage Differential. See

SCSI

.

RAW

see

read-after-write

read-after-write

RAW improves data integrity by reading data immediately after it is written and

writing the data again if an error is found.

reserved

Not generally available for use with the drive. A reserved field should contain all

zero bits.