Sony DDS-4, Руководство по описанию продукции

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6 - 13 SONY SDT-10000/SDT-11000 DDS Tape Drive
6. COMMAND SPECIFICATION
Value Type of Parameter Values
00b Current Threshold Values
01b Current Cumulative Values
10b Default Threshold Values
11b Default Cumulative Values
PC: The Page Control field defines the type of parameter values to be selected:
LOG SELECT
Table 6-3: Page Control field values
If this field is set to 00b, 10b or 11b and the Parameter List Length field is non-0 then the command will be terminated
with a CHECK CONDITION status with the sense key set to ILLEGAL REQUEST, and an additional sense code of
INVALID FIELD IN CDB. This is because no modification of these log pages are permitted.
For a description of command action if this field is set to 01b then see the description of the Parameter List Length field
below.
If this field is set to 10b and the Parameter List length field is 0 then all Current Threshold Values will be reset to the
Default Threshold Values. This equivalent to no change as Threshold Values cannot be modified.
If this field is set to 11b and the Parameter List Length field is 0 then all Current Cumulative Values will be reset to the
Default Cumulative Values.
This is equivalent to all log pages which can be cleared.
Parameter List Length:
This field specifies the length in bytes of the LOG SELECT parameter list that shall be transferred from the initiator to
the target during the DATA OUT phase. A parameter list length of zero indicates that no data shall be transferred. This
condition shall not be considered as an error (see description of Parameter Code Reset and Page Control fields above). If
this field is non-0 the Page Control field must be 01b.
The purpose of the LOG SELECT command is to allow the initiator to modify and initialize parameters within the logs
supported by the device. However in this case, access to individual parameters within log pages is not supported and so
initiator is restricted to resetting complete log pages only.