Data storage device integrating wedge repeatable runout (WRRO) learning into data recovery procedure (DRP)
A data storage device comprises a disk having a plurality of data tracks and a plurality of servo wedges wherein the plurality of servo wedges comprise a plurality of wedge repeatable runout (WRRO) fields configured to store a plurality of WRRO compensation values in connection with the plurality of data tracks. The data storage device may also include a read/write head configured to be actuated over the disk, and a controller configured to gather position error signal (PES) data needed for computation of the WRRO compensation values during a field operation of the data storage device. The data storage device may be further configured to adjust a position of the read/write head based on the WRRO compensation values.
1. A data storage device comprising:
a disk comprising a plurality of data tracks and a plurality of servo wedges, wherein the plurality of servo wedges comprise a plurality of wedge repeatable runout (WRRO) fields configured to store a plurality of WRRO compensation values in connection with the plurality of data tracks;
a read-write head configured to be actuated over the disk; and
a controller configured to:
gather position error signal (PES) data needed for computation of the WRRO compensation values during a field operation of the data storage device during a data recovery procedure (DRP) that is invoked when an error condition occurs, and
adjust a position of the read-write head based on the WRRO compensation values.
2. The data storage device of claim 1 , wherein the field operation comprises a complete revolution of the disk.
3. The data storage device of claim 1 , wherein the error condition is a write inhibit condition or a read inhibit condition.
4. The data storage device of claim 3 , wherein the controller is further configured to compute updated WRRO compensation values from the PES data gathered during the DRP and to use the updated WRRO compensation values in a retry of a write operation or a read operation.
5. The data storage device of claim 4 , wherein the controller is further configured to store the updated WRRO compensation values for future operations.
6. The data storage device of claim 4 , wherein the controller is further configured to replace original WRRO compensation values computed during a manufacturing process of the data storage device with the updated WRRO compensation values.
7. A method for performing a wedge repeatable runout (WRRO) learning process for a data storage device, comprising:
actuating a read-write head over a data track of a disk of a data storage device to perform a read operation or a write operation;
detecting an error condition while performing the read operation or the write operation;
performing a data recovery procedure (DRP) to resolve the error condition; and
while the DRP is being performed, controlling the read-write head to gather position error signal (PES) data needed for computation of WRRO compensation values.
8. The method of claim 7 , wherein performing the DRP comprises effecting a complete revolution of the disk.
9. The method of claim 7 , wherein the error condition is a write inhibit condition or a read inhibit condition.
10. The method of claim 9 , further comprising:
computing updated WRRO compensation values from the PES data gathered during the DRP; and
using the updated WRRO compensation values in a retry of the read operation or the write operation.
11. The method of claim 10 , further comprising:
storing the updated WRRO compensation values for future operations on the data track.
12. The method of claim 10 , further comprising:
replacing original WRRO compensation values computed during a manufacturing process of the data storage device with the updated WRRO compensation values.
13. A data storage device comprising:
means for storing a plurality of wedge repeatable runout (WRRO) compensation values in association with a plurality of data tracks on a disk;
means for gathering position error signal (PES) data needed for computation of the WRRO compensation values during a field operation of the data storage device, and wherein the means for gathering the PES data is configured to gather the PES data during a data recovery procedure (DRP) that is invoked when an error condition occurs; and
means for adjusting a position of a read-write head for writing data to and reading data from the disk based on the WRRO compensation values.
14. The data storage device of claim 13 , wherein the field operation comprises a complete revolution of the disk.
15. The data storage device of claim 13 , wherein the error condition is a write inhibit condition or a read inhibit condition.
16. The data storage device of claim 15 , further comprising:
means for computing updated WRRO compensation values from the PES data gathered during the DRP; and
means for using the updated WRRO compensation values in a retry of a write operation or a read operation.
17. The data storage device of claim 16 , further comprising means for storing the updated WRRO compensation values for future operations.
18. The data storage device of claim 16 , further comprising means for replacing an original WRRO compensation value computed during a manufacturing process of the data storage device with the updated WRRO compensation values.