HP Q153090901 - Manual (Page 168)

Commands 168
SEND DIAGNOSTIC 1Dh
S END DIAGNOSTIC tells the drive to perform either its standard self-test, or diagnostics specified in
the parameter list on itself. The parameter list is transferred to the drive in a series of data-out
phases; each 8-byte data-out phase specifies a diagnostic to be performed by the drive. It is not
an error to set Self-Test = 0 and to have a zero-length parameter list.
The test results can be retrieved with the RECEIVE DIAGNOSTIC RESULTS command.
Pre-execution checks:
• If Self-Test = 0, the UntOffl bit must be set, otherwise CHECK CONDITION is reported. Sense
data will be as described in Illegal Field Checks.
• If Self-Test = 1, the Parameter List Length field must be zero. Otherwise CHECK CONDITION is
reported. Sense data will be as described in Illegal Field Checks.
• It is not an error to set Self-Test = 0 and to have a zero-length parameter list.
Command descriptor block:
CDB fields:
Illegal Field Reservation Deferred Error Unit Attention
7 6 5 4 3 2 1 0
0 Operation Code (1Dh)
1 Reserved (0) PF (1) Rsvd(0) Self-Test DevOffL(0) UnitOffL
2 Reserved (0)
3 (MSB)
Parameter List Length
4 (LSB)
5 Control
PF Page Format. Specifies that the accompanying data follows the SCSI-3 Diagnostic Page
format. It must be set to 1.
Self-Test 0 Perform the diagnostics specified in the parameter list. The UnitOffL bit must be
set, otherwise CHECK CONDITION is reported. The drive reports status when the
command has been completed.
1 Perform the standard self-test depending on the value of UnitOffL (see above).
The Parameter List Length must be 0 otherwise CHECK CONDITION is reported.
The drive will report GOOD status following the pre-execution checks and before
executing the command.
DevOffl Device Offline bit. Must be cleared to zero.
UnitOffL Unit Offline bit
0 Indicates that the host is not prepared for the drive to perform tests that could
affect logical position.