Quantum 7000DLT Series, Руководство по эксплуатации продукта

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SCSI Commands
Quantum DLT 7000 Tape System 5-147
REQUEST SENSE Command (03h) (continued)
Table 5–70 REQUEST SENSE Data - Field Descriptions
Field Name Description
Valid When set to 1, this field indicates that the information bytes contain valid
information as defined in the ANSI SCSI-2 specification.
Error Code A value of 70h indicates a current error – the report is associated with the
most recently received command.
A value of 71h indicates a deferred error – the report is associated with a
previous command and not as a result of the current command.
No other values are returned in this field.
Segment Number This value of this byte is always 0.
Filemark This bit indicates that the current command has read a Filemark.
EOM End of Medium. This bit indicates that an End of Medium condition (End of
Partition or Beginning of Partition) exists. The warning is also given by setting
the Sense Key to NO SENSE and the Additional Sense Qualifier to End of
Partition or Beginning of Partition.
ILI Incorrect Length Indicator. This bit indicates that the requested logical block
length did not match the logical block length of the data on the tape
medium. Only READ or VERIFY may cause this bit to be set.
Sense Key In most cases, Additional Sense Code and/or Qualifier information is available.
The codes and qualifiers are covered in detail in Table 5-72.
Information Bytes These bytes contain the differences (residue) of the requested length minus
the actual length in bytes, blocks, or Filemarks, as determined by the
command. Negative values are indicated by two’s complement notation. The
bytes are valid for all READ, WRITE, SPACE, and VERIFY tape commands for
which a CHECK CONDITION status has been generated. The information bytes
are 0 for MODE SELECT / SENSE, INQUIRY, READ BLOCK LIMITS, and TEST UNIT
READY.
Additional Sense
Length This field specifies the number of additional sense bytes to follow. If the
Allocation Length of the Command Descriptor Block is too small to transfer all
of the Additional Sense bytes, the Additional Sense Length is not adjusted to
reflect the truncation.
Command Specific
Information Bytes Command Specific Information Bytes can be logged by the operating system
on error conditions. On tape medium errors, such an entry usually contains
the current SCSI Logical Block Address.