Quantum 7000DLT Series, Руководство по эксплуатации продукта

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SCSI Commands
Quantum DLT 7000 Tape System 5-169
WRITE Command (0Ah) (continued)
Table 5–82 WRITE Command Data — Field Descriptions (continued)
Field Name Description
Fixed (cont.) When the Fixed bit is 1, the Transfer Length field specifies the number of blocks to
be transferred to the host beginning at the current tape position. This form of WRITE
is valid only if the logical unit is currently operating in the Fixed Block mode – 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.
Transfer
Length This field contains the length of the data transfer in bytes or blocks depending on
whether Fixed or Variable block mode is selected.
When the Transfer Length is 0, no data is transferred and the current position on the
logical unit is not changed.
Exception Conditions
If End of Tape (EOT) is detected while writing, the tape drive finishes writing
any buffered data. The command terminates with CHECK CONDITION status.
Within the sense data, the EOM bit is set, the Sense Key is set to NO SENSE,
and the Additional Sense code and Additional Sense Code Qualifier fields are set
to EOM/P detected. The drive attempts to complete any subsequent writes,
returning a CHECK CONDITION status in each case.
If the tape drive encounters the physical End of Medium (EOM) when
attempting WRITE, a CHECK CONDITION status is returned. Within the sense
data, the EOM and Valid bits are set, and the Sense Key field is set to Volume
Overflow. The Information fields contain the residue count and the Additional
Sense code and Additional Sense Code Qualifier fields are set to EOM/P
Detected. The tape is physically positioned at EOM/P.