Tandberg Data SLR7-140 PROGRAMMER, Руководство пользователя

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Tandberg Data Write
30-3 Tandberg SLR Product Line SCSI Functional Specifications
30.5. Write from EOD, Append
If the WRITE command follows a LOCATE, READ, SPACE, VERIFY,
WRITE FILEMARKS or another WRITE command, and the tape is
positioned for a data append, the write operation will
start at the current tape position
.
30.6. Writing Over Existing Data, Overwrite
The Drive may in certain cases allow a limited possibility
for overwrite. See section 2.5 Overwrite for details
.
30.7. Terminating Write Operations
When writing on a tape, the write operation must be
properly terminated before the cartridge is suitable for
reading on the same or any other Drive. The cartridge is
suitable for reading when all the buffered data (and
tapemarks) and an end-of-data marker is written to the
tape. If necessary, FILLER blocks are padded to fill up the
last frame written. For some medium types (
SLRtape140 to
SLRtape7 or SLR32 ) it will also be necessary to update the
Media Header information located near the BOM marker on the
loaded medium.
The following commands will force all the buffered data
(and tapemarks) and the end-of-data marker to be written to
the tape:
„
LOAD/UNLOAD
„
LOCATE
„
REWIND
„
SPACE
„
WRITE FILEMARKS (if IMMEDIATE bit not set)
„
WRITE FILEMARKS (if Number of Filemarks is zero)
If the Drive is configured to unbuffered mode, WRITE
commands will not terminate before all data transferred
from host is written to the tape. This will reduce the
performance
.
Note:
When the Drive is in unbuffered mode the actual capacity
of a tape may be much less than specified if the
Transfer Length of the write command is small. This is
because FILLER blocks are used to fill the last frame of
all WRITE commands.
The following commands will perform a Media Header update:
„
LOAD/UNLOAD
„
REWIND
The Drive will ensure that a cartridge may not be ejected
without terminating the write operation properly. If eject
is requested (either by pressing the Eject Button or by
issuing an UNLOAD command), the buffered data (and
tapemarks) and an end-of-data marker are written to the
tape. The tape is then rewound to BOT and the Media Header
is updated. Finally the cartridge is physically ejected.