Quantum 7000DLT Series, Руководство по эксплуатации продукта

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SCSI Commands
5-128 Quantum DLT 7000 Tape System
5.12 READ COMMAND (08h)
This command transfers one or more data blocks or bytes to the initiator
starting with the next block on the tape.
Bit
Byte
7 6 5 4 3 2 1 0
0 Operation Code (08h)
1 Logical Unit Number Reserved SILI Fixed
2 - 4
(MSB)
Transfer Length
(LSB)
5 Unused Reserved Flag Link
Figure 5–61 READ Command Descriptor Block - Data Format
Table 5–61 READ Command Descriptor Block - Field Descriptions
Field Name Description
SILI Suppress Incorrect Length Indicator. If the SILI bit is set to 1 and the Fixed bit is set to
1, the target terminates the command with CHECK CONDITION status, sense key set
to ILLEGAL REQUEST, and additional sense code of INVALID FIELD IN CDB.
If the SILI bit is 0 and the actual block length is different than the specified transfer
length, a CHECK CONDITION status is returned. Within the sense data, the Incorrect
Length Indicator (ILI) bit and Valid bit will be set to 1. The sense key field specifies
NO SENSE. The information bytes are set to the difference (residue) between the
requested transfer length and the actual block length., or, in Fixed Block mode, the
difference (residue) between the requested number of blocks and the actual number
of blocks read. No more than transfer length blocks are transferred to the initiator
and the tape is logically positioned after the block (EOM side).