Sony AIT-SDX460, Руководство по техническим характеристикам продукции

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LOG SELECT 7. ATAPI Packet Command Specification
SONY AIT-1Turbo drive SDX-460V series Ver.1.0 7-9
7.5. LOG SELECT 4Ch
Bit
Byte
7 6 5 4 3 2 1 0
0 Operation Code (4Ch)
1 Reserved PCR SP (0)
2 PC Reserved
3 Reserved
4 Reserved
5 Reserved
6 Reserved
7 (MSB)
8
Parameter List Length
(LSB)
9 Reserved
10 Reserved
11 Reserved
The LOG SELECT command provides a means for the Host to manage statistical information maintained by the
device about its own hardware or the installed media. This description should be read in conjunction with the
description of the LOG SENSE command which follows it, to provide the reader with information about log page
format, parameters and supported pages.
PCR: A Parameter Code Reset bit of one and a Parameter List Length of ZERO will cause ALL log pages which
can be cleared, to be cleared. If this field is set and the Parameter List Length field is non-ZERO 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.
SP: The device does not have non-volatile RAM into which it may save parameters. Therefore, the Save Page bit
is not supported by this device and shall always be set to ZERO. If the SP bits is set, the command will be
terminated with CHECK CONDITION status with the sense key set to ILLEGAL REQUEST, and an additional
sense code of INVALID FIELD IN CDB.
PC: The Page Control field defines the type of parameter values to be selected:
Table 7-7: LOG PAGE Page Control Field Values
Value Description
00b Current Threshold Values
01b Current Cumulative Values
10b Default Threshold Values
11b Default Cumulative 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 behavior 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 is 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.