Sony SDX-1100V Series, Руководство пользователя

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WRITE 0Ah 6.Command Specification
SONY AIT-5 drive SDX-1100V series Ver.1.0 6-103
6.29.
WRITE 0Ah
Bit
Byte
7 6 5 4 3 2 1 0
0 Operation Code (0Ah)
1 Reserved Fixed
2 (MSB)
3 Transfer Length
4 (LSB)
5 Control
The WRITE command requests that the drive write the data that is transferred from the initiator to the logical
position.
Fixed: The Fixed bit specifies whether fixfed-length or variable-length blocks are to be transferred.
If the Fixed bit is set to ZERO, Variable Block mode is selected. A single block is transferred from the initiator and
is written to the current logical tape position. If the WRITE command complete successfully, the tape is logically
positioned after this block(EOM/P side).
If the Fixed Bit is set to one, the Transfer Length field specifies the number of blocks to be transferred to the
current logical position. This is valid only if the drive is currently operating in Fixed Block mode, in other words,
when it has been instructed to use fixed-length blocks with MODE SELECT. The current block length is the block
length defined in the MODE SELECT command. Upon termination, the tape is logically positioned after these
blocks (EOM/P side).
If the EARLY-WARNING is detected while writing, the drive will finish writing any buffered data. The command will
terminate with a CHECK CONDITION status., The EOM bit is set and the Sense Key field in the Sense Data is set
to NO SENSE and the ASC and ASCQ fields are set to EOM/P detected. The drive will attempt to complete any
subsequent writes, returning a CHECK CONDITION status in each case.
If the drive encounters the physical EOM when attempting a WRITE, a CHECK CONDITION status is returned.
The EOM and Valid bits are set and the Sense Key field in the Sense Data is set to VOLUME OVERFLOW. The
Information field contains the residue count and the ASC and ASCQ fields are set to EOM/P Detected. The tape is
physically positioned at EOM/P.
If the Transfer Length is ZERO, no data will be transferred and the current position on the logical unit will not be
changed.
The drive flushes its write buffer to tape and appends an EOD under the following conditions:
1.
Receipt of the following non-write commands:
READ
SPACE
ERASE
READ BUFFER
WRITE BUFFER
REWIND
LOAD/UNLOAD
MODE SELECT (Media Operation)
LOCATE
The buffer can be maintained through the following media commands, assuming that no other flush condition has
been met, for example, write hold-off time-out.
WRITE
WRITE FILEMARKS (except count field of 0)
2.
The write hold-off time limit is exceeded.