IBM Ultrastar 36LZX, Specifications

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11.17 Diagnostics
The drive will execute a self test at power on or when a Send Diagnostics command is issued with the
self test bit set.
The diagnostics are to assure the correct operation of the drive and to verify that the check circuits
detect fault conditions.
11.17.1 Power on Diagnostics
At power on time the following tests are executed:
1. ROM code verification.
2. RAM size verification.
3. Test and Initialize HDC registers.
4. Sector buffer RAM read/write test.
5. Sector buffer clean up.
6. Start spin-up (if Auto-spin enable).
7. Release actuator.
8. Calibration.
9. Read reserved data for RAM code and data table.
10. Activate RAM code.
11. RDM/LOG/MODE table verification.
11.17.2 Diagnostics Command
The tests executed as a result of the Send Diagnostics command with the self test bit set to one differs
from the tests executed at power on. The spindle motor must be at the correct speed for the Diagnostics
command to be executed. If the motor is not at the correct speed, a NOT READY status will be returned
in the sense byte.
The Diagnostics command will execute the following tests:
1. Test the adapter section of the drive as follows:
a. Assure the ECC circuits work correctly.
b. Do a read/write test on sector buffer RAM.
2. Check the RPM of the spindle.
3. Seek a correct cylinder.
4. Write to a certain area in reserved area.
5. Read from the area.
11.17.3 Diagnostics Fault Reporting
Faults detected before successful completion of the adapter section could prevent the drive from
responding to a selection.
Faults detected after the successful completion of the adapter section will be reported as Check Con-
dition status to the initiator on the first command issued after a fault is detected except for the Inquiry
command. The Inquiry command will always respond with good status. Detecting a fault during power on
will not terminate execution of the diagnostics nor will it terminate the power on process.
Faults detected during a Send Diagnostics command will report a Check Condition as end status.
Ultrastar 36LZX hard disk drive specifications
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