Fibre Channel Interface Manual, Rev. D 191
The parameter values returned are from one of the following:
The specified parameter values in the log counters as of the last update (updated by Log Select command, Log Sense
command or done automatically by the drive for cumulative values).
If saved values are available, the saved values are used after the last LIP reset.
If saved values are not available, the default values are used after the last LIP reset.
Parameter Pointer
A parameter code (see Table 128) that specifies that log parameter data be returned to the initiator starting with the Param-
eter Pointer code and continuing to the maximum allocation length or to (and including) log parameter data of the maximum
parameter code supported by the drive, whichever is less. If the value of the Parameter Pointer field is larger than the larg-
est available parameter code that can be returned by the drive on the specified page, the drive terminates the command
with a Check Condition status. The sense key is set to Illegal Request and the additional sense code is set to Invalid Field
In CDB.
PPC (Parameter Pointer Control)
1 The drive returns a log page with only those log parameters that have changed since the last Log Select or Log
Sense command. The drive returns log parameter codes according to (in ascending numerical order) the parameter
code specified in the Parameter Pointer field (bytes 5 & 6).
0 All of the log parameter data requested from the drive, whether changed or not, is sent and it begins with the log
specified by the parameter code given in the Parameter Pointer field and returns the number of bytes specified by
the allocation length field, in ascending order of parameter codes starting at the parameter code given in the Param-
eter Pointer field.
A PPC bit of zero and a Parameter Pointer field of zero causes all available log parameters for the specified log
page to be returned to the initiator subject to the allocation length.
SP (Save Parameters)
0 The drive performs the specified Log Sense command and does not save any log parameters to nonvolatile mem-
ory.
1 The drive first saves parameters identified as savable (by the DS bit in Table 124) to a nonvolatile location, and then
performs the rest of the Log Sense command.
Table 123: Log Page format
Bit
Byte
76543210
0Reserved Page Code
1 Reserved
2(MSB) Page Length (n–3)
3(LSB)
Log parameter structure(s)
4 to
x + 3
Log Parameter (First)
(Length X bytes)
..
..
..
n–Y Log Parameter (last)
(Length Y bytes)
122
122
122