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[5]
Enable Threshold Comparison (ETC). A one indicates that a comparison to the threshold value is per-
formed whenever the cumulative value is updated. A bit of zero indicates the comparison is not performed.
The value of the ETC bit is the same for both the threshold and cumulative parameters.
[6]
The Threshold Met Criteria (TMC) field defines the basis for comparison of the cumulative and threshold
values. See Table 72 for meanings of values in this field. The TMC field is only valid when the ETC bit is
one.
Table 72:
Threshold Met Criteria
Code
Basis for Comparison
00b
Notify of every update of cumulative value
01b*
Cumulative value equal to threshold value
10b*
Cumulative value not equal threshold value
11b*
Cumulative value greater than threshold value
*Comparison made at every update of cumulative value.
If the ETC bit is one* and the result of the comparison is true, a Unit Attention Condition is generated for
all initiators. When reporting the Unit Attention Condition, the drive sets the sense key to Unit Attention,
and the additional sense code to Threshold Condition Met.
*The RLEC bit (Report Log Exception Condition) in Mode page 0AH (Table 96) must also be one.
[7]
List Parameter (LP). Zero indicates the parameter is a data counter. One indicates that the parameter is a
list parameter. This bit only has meaning for the Log Sense command Data In pages.
Data counters are associated with one or more events. The data counter is updated whenever one of
these events occurs by incrementing the counter value, provided the DU bit is zero. See note [2] for this
table.
An LP bit of one indicates that the parameter is a list parameter. List parameters are not counters and thus
the ETC and TMC fields shall be set to zero. A list parameter is a string of ASCII graphic codes (i.e., code
values 20h thru 73h). List parameters are not supported by the drive at this time.
[8]
Parameter Length. This field specifies the length in bytes of the parameter that follows. If the initiator
sends a Parameter Length value that results in the truncation of the Parameter Value, the drive terminates
the command with a Check Condition status. The sense key shall be set to Illegal Request with the addi-
tional sense code set to Invalid Field In Parameter List.
[9]
Parameter Value. This field uses one, two, four, or eight bytes to transmit an unsigned counter value. The
initiator sends counts to set values into counters in the drive, and the drive returns counter values to the
initiator. The initiator is responsible to issue a Log Sense command to learn the Parameter Length the tar-
get has selected.
When any counter in a log page reaches its maximum value, the drive ceases incrementing all counters in
that log page. If the RLEC bit of the Control Mode page is one, then the drive reports the exception condi-
tion as described in note [2] of this table.
SCSI Interface Product Manual, Rev. J
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