Quantum LTO 4, Руководство пользователя

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SCSI Commands: 21BLOG SENSE Page 51
3.9.3.1 Log Page Header
Byte
Bits
7 6 5 4 3 2 1 0
0 Reserved Page Code
1 Reserved
2 (MSB)
3
Page Length
(LSB)
3.9.3.2 Log Page Field Descriptions
Field Bytes Bits Description
Page
Code 0 0-5 Identifies the page being returned.
Page
Length 2-3 Indicates the length of the page in bytes that follow the page header. If
the allocation length specified in the CDB is too small to transfer the
entire requested page, this value is not adjusted to reflect the
truncation. However, if the Parameter Pointer field specifies a starting
parameter code other than zero, the page length is adjusted to
indicate the number of bytes that follow the page header.
Reserved All reserved bits must be 0.
3.9.3.3 Log Parameter
Byte
Bits
7 6 5 4 3 2 1 0
0 (MSB)
1
Parameter Code
(LSB)
2 DU DS TSD ETC TMC LBIN LP
3 Parameter Length
4 – n Parameter Value
3.9.3.4 Log Parameter Field Descriptions
Field Bytes Bits Description
Parameter
Code 0-1 Identifies the log parameter returned. Log Parameters are always
returned in ascending order.
Disable
Update
(DU)
2 7
0 = Enables update of accumulated value when the corresponding
event occurs.
1 = Disables update of all accumulated values within a log page when
the corresponding event occurs. The drive sets this bit to indicate
that the accumulated value of the parameter has reached its
maximum value so that the drive can no longer increment any
Parameter Values.
Disable
Save (DS) 2 6 Always 1, indicating that the drive does not support Save Page in LOG
SENSE and LOG SELECT.
TSD 2 5 Always 0, indicating that Target Save Disable (TSD) is not supported.
ETC 2 4 Always 0, indicating that Enable Threshold Comparison (ETC) is not
supported.
TMC 2 2-3 Always 0, indicating that Threshold Met Criteria (TMC) is not
supported.
List Binary
(LBIN) 2 1 Always 0, indicating that all log parameters are data counters.