Log sense 4dh, Pre-execution checks, Command descriptor block – HP Q153090901 User Manual
Page 57: Cdb fields, Log sense dh 57, Command descriptor block: cdb fields
LOG SENSE 4Dh
C
omm
an
ds
57
LOG SENSE
4Dh
LOG SENSE
allows the host to read the drive’s logs. A single log is returned with each invocation of
LOG SENSE
.
Pre-execution checks:
The Page Code must match one of the supported log page codes. If it does not, then
CHECK
CONDITION
status is reported. Sense data will be as described in the Illegal Field Checks.
Command descriptor block:
CDB fields:
Illegal Field
Deferred Error
Unit Attention
7
6
5
4
3
2
1
0
0
Operation Code (4Dh)
1
Reserved (0)
PPC (0)
SP (0)
2
PC
Page Code
3
Reserved (0)
4
5
Parameter Pointer
6
7
(MSB)
Allocation Length
8
(LSB)
9
Control
PC
The Page Control field defines the type of log parameter to be returned:
00b Current Threshold Values—any parameters in the log that are counters contain
the maximum value that they can count to.
01b Current Cumulative Values—any parameters in the log that are counters contain
their current counts.
NOTE:
Counts are reset to their default cumulative values (see below) following a
power-on, reset or bus device reset. Media related counts are also reset following
a load.
10b Default Threshold Values—same as the Current Threshold Values
11b Default Cumulative Values—any parameters in the log that are counters contain
the initial values of those counters (set at power-on, reset, bus device reset and, in
the case of media logs, load).
The PC field has no effect on the data returned when the selected log contains event or
trace codes rather than counts.
Page Code
The Page Code field identifies which log page is being requested by the host. See
page 59 for the list of valid page codes.