Multi-sector read offset recovery
An integrated circuit includes a read/write channel and a servo controller. The read/write channel is configured to: determine, in connection with a first path, respective read errors associated with N number of the data sectors; estimate respective offset positions of the N number of the data sectors; and generate a second path based, at least in part, on the respective estimated offset positions. The servo controller is configured to cause adjustment of a position of a read transducer based on the second path.
1. A method comprising:
determining an error while attempting to read certain data sectors in a first data track while following a first path;
estimating an offset position of each of the certain data sectors;
generating a second path for a read transducer to follow to read data from the certain data sectors based, at least in part, on the estimated offset position; and
attempting to reread data from the certain data sectors while following the second path, wherein the data sectors are non-consecutive with respect to each other.
2. The method of claim 1 , wherein the estimated offset position includes a direction.
3. The method of claim 2 , wherein the direction includes either a positive radial direction or a negative radial direction.
4. The method of claim 1 , wherein the offset position is based on a positive or negative percentage of a pitch of the first data track.
5. The method of claim 1 , wherein the first path is along a centerline of the first data track.
6. The method of claim 1 , wherein the attempting is carried out in a single revolution of a data storage medium for all missed data sectors of the data track.
7. The method of claim 1 , further comprising:
generating a third path.
8. The method of claim 7 , wherein the third path is generated to pass over any remaining missed data sectors after following the second path.
9. The method of claim 7 , wherein the third path is based, at least in part, on an average estimated offset position.
10. A hard disk drive comprising:
a magnetic recording medium comprising data sectors along a data track;
a read/write head comprising a read transducer; and
an integrated circuit including circuitry programmed to:
determine, in connection with a first path, respective read errors associated with N number of the data sectors of the data track,
estimate respective offset positions of the N number of the data sectors of the data track, and
generate a second path along the same data track based, at least in part, on the respective estimated offset positions.
11. The hard disk drive of claim 10 , wherein the circuitry is further programmed to:
adjust the read/write head to follow the second path.
12. The hard disk drive of claim 11 , wherein the circuitry is further programmed to:
determine, in connection with the second path, respective read errors of a subset of the N number of the data sectors, and then
generate a third path.
13. The hard disk drive of claim 12 , wherein the third path is based, at least in part, on an average of estimated offset positions.
14. The hard disk drive of claim 10 , wherein the second path crosses a centerline of the data track and passes over a servo sector.
15. A system-on-a-chip (SOC) comprising:
a read/write channel configured to:
determine, in connection with a first path, respective read errors associated with N number of the data sectors,
estimate respective first offset positions of the N number of the data sectors,
generate a second path based, at least in part, on the respective estimated first offset positions,
determine, in connection with the second path, respective read errors associated with a subset of the N number of the data sectors,
estimate respective second offset positions of the subset, and
generate a third path; and
a servo controller configured to:
cause adjustment of a position of a read transducer based on the second path.
16. The SOC of claim 15 , wherein the read/write channel is configured to generate the third path based, at least in part, on the respective first offset positions associated with the subset, the respective second offset positions, and the second path.
17. The SOC of claim 15 , wherein the read/write channel is configured to generate a fourth path, wherein the third path is designed to pass over a first subset of the N number of the data sectors, wherein the fourth path is designed to pass over a second subset of the N number of the data sectors.
18. The SOC of claim 17 , wherein the first subset and the second subset are mutually exclusive subsets of the data sectors of mutually exclusion.
19. The SOC of claim 15 , wherein the first path, the second path, and the third path are along the same data track.
20. The SOC of claim 15 , wherein the third path is based, at least in part, on an average estimated offset position.