Sony SDX-800V/R manual Supported Log Pages, Threshold Met criteria, Tmc, Threshold Met Criteria

6.Command Specification LOG SENSE

TSD: A target save disable (TSD) bit of ZERO indicates a target-defined method for saving log parameters. This implicit saving operation shall be done frequently enough to insure that the cumulative parameter values retain statistical significance (i.e. across power cycles). A TSD bit of one indicates that either the target does not provide a target-defined method for saving log parameters or the target-defined method has been disabled by the initiator. If the initiator sets both the DS and the TSD bits set to one, the target shall terminate the command with CHECK CONDITION status. The sense key shall be set to ILLEGAL REQUEST with the additional sense code set to

INVALID FIELD IN PARAMETER LIST.

ETC: An enable threshold comparison (ETC) bit of one indicates that when the cumulative parameter value is updated, it shall be compared to the threshold parameter value and the action specified by the TMC field shall be taken. An (ET) bit of ZERO disables this comparison. The ET bit is the same for both the cumulative and threshold log parameter. Thus when the ET bit is set to a value by the initiator, this value is returned for both the cumulative and threshold values of the log parameter.

TMC: The threshold met criteria (TMC) field defines the binary relationship between the cumulative and threshold log parameter values under which the threshold is met. If the ET bit is one and the threshold condition is met, a Unit Attention condition shall be posted to all initiators. When reporting the unit attention condition, the target shall set the sense key to UNIT ATTENTION, the additional sense code to LOG EXCEPTION, and the additional sense code qualifier to THRESHOLD CONDITION MET.

The TMC field is the same for both the cumulative and threshold parameter. Thus when the TMC field is set to a value by the initiator, this value is returned for both cumulative and threshold values of the log parameter.

	Table 6-12: Threshold Met criteria
TMC	Threshold Met Criteria
00b	Any update of the parameter
01b	Cumulative = Threshold
10b	Cumulative < > Threshold
11b	Cumulative > Threshold

LP: The LP bit field defines whether the parameter is a data counter or a list parameter. See the description of each supported page below for information on the setting of this field.

Note: If any of the other bit-fields in the control byte are set then the command will terminate with a CHECK CONDITION status with a sense key of ILLEGAL REQUEST and an additional sense code of INVALID FIELD IN PARAMETER LIST

6.6.3. Supported Log Pages

The following log pages are supported:

	Table 6-13: Supported Log pages
Page Code	Description
00h	Supported Log Pages
02h	Write Error Counter Page
03h	Read Error Counter Page
07h	Last n Error Events Page
2Eh	Tape Alert Log Page
30h	Tape Log Page (Sony Unique)
31h	Tape Capacity Log Page
33h	Drive Usage Log Page (Sony Unique)
34h	Write Frame Error Counter Page
35h	Read Frame Error Counter Page
39h	Transfer Log Page
3Ch	AIT Log Page
3Dh	AIT Fixed Length Information Page for MIC
3Eh	AIT Variable Length Information Page for MIC

A description of each supported log page is given below.

6-16 SONY AIT-3Ex drive SDX-800V series Ver.1.1