Quantum DLTtape DLT 4000, Product Manual

Page: 237 / 300

SCSI Commands
Quantum DLT 4000 Tape Drive 5-137
REQUEST SENSE Command (03h) (continued)
Table 5–66 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 5-67.
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.