Commands 145
Commands
SEND DIAGNOSTIC 1Dh
SEND 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.
