HGST HUS724040ALS640 User Manual

HGST Ultrastar 7K4000 (SAS) Hard Disk Drive Specification
98
18.6 LOG SELECT (4C)
Table 67: Log Select (4C)
The LOG SELECT command provides a means for the Initiator to clear statistical information maintained by the drive and
reported via the LOG SENSE command.
• PCR The Parameter Code Reset determines whether the Log Sense parameters will be cleared and unit attention posted
for all other Initiators. A value of 1 indicates that the parameters be cleared, while a value of zero (except when PC =
11b) indicates that the parameters not be cleared. Parameter list length must be zero when PCR is 1. The PC field is
ignored for list parameters, i.e. when the Format and Linking (F&L) field contains 01b or 11b.
• SP The Save Parameters bit value of zero indicates that the page parameters not be saved. A value of 1 indicates that the
page parameters that are savable be saved after they have been changed. SP bit MUST be 1 if parameter list length is
greater than zero. Otherwise it will result in a Check Condition status being returned. The sense key shall be set to
Illegal Request and additional sense code of Invalid Field in CDB.
• PC The Page Control field defines the type of parameters to be selected. The PC field set to 11b (and PCR is then a don't
care) indicates that the Default Cumulative values are set to their default values of 0. If the PC field is set to 01b and
PCR is set to 1, the Current Cumulative values are also set to their default values of 0.
Parameter List Length MUST be zero when PC = 11b. Otherwise the command is terminated and a Check Condition
status is returned. The sense key shall be set to Illegal Request and additional sense code of Invalid Field in CDB.
•Page Code field identifies which page is being selected. This field must be set to the values indicated in Page 0. If the
Page Code value is invalid a Check Condition status is returned with a sense key of Illegal Request and additional
sense code of Invalid Field in CDB.
• If page code field is set to zero, then the selection applies to all log parameters in all valid log pages.
• If page code field is set to a non zero, then the selection applies to all log parameters specified by this field.
•SubPage Code This field specifies the subpage to select. This field is not supported and must be set to 0.
• Parameter List Length The Parameter List Length field specifies the length in bytes of the parameter list that shall be
located in the DATA OUT buffer. A parameter list length zero indicates that no pages shall be transferred.
• If the PARAMETER LIST LENGTH field is set to zero, then the PCR bit, the SP bit, and the PC fields apply to
the page (pages) addressed by the page code field.
• If The PARAMETER LIST LENGTH field is set to non zero, and the if PAGE CODE field is non-zero or the
SUBPAGE CODE field is non-zero, then the command shall be terminated with CHECK CONDITION status, with the
sense key set to ILLEGAL REQUEST, and the additional sense code set to INVALID FIELD IN CDB.
Byte
Bit
76543210
0 Command Code = 4Ch
1 Reserved = 0 Reserved = 0 PCR SP
2 PC Page Code
3 SubPage Code = 0
4-6 Reserved = 0
7
8
(MSB)
Parameter List Length = 0
(LSB)
9 Reserved = 0 FLAG LINK

HGST HUS724040ALS640 Specifications

General

Brand	HGST
Model	HUS724040ALS640
Category	Storage
Language	English