System and method of synchronized writing on bit patterned media with read-write offset
AssigneeHGST Netherlands B.V.
InventorsToshiki Hirano, Xiaotian Sun
Life of this patent
Estimating the term…
Abstract
A system and method of establishing write timing in a disk drive using bit patterned media and a magnetic head with read-write offset in which servoing and writing occur on different tracks with timing offsets. Initially, the distance between the servoing and writing tracks is determined for each track/head position in accordance with head geometry and skew angle. The relative timing errors are then measured by iteratively writing data at timing offset increments to determine the optimal timing offset for the servoing/writing track pair, and then writing the offset to sync fields on the servoing tracks of the disk.
Claims17
A method for synchronizing writing in a disk drive, comprising:
- providing the disk drive with a disk having bit patterned media, and a slider with a read head and a write head for reading data from and writing data to the disk, respectively;
- positioning the read head at a read-write offset with respect to the write head;
- writing data with the write head onto a data pattern on a write track of the bit patterned media;
- providing a timing offset between the data pattern on the write track and a data pattern on a servoing track of the bit patterned media with the read head using the data pattern on the servoing track;
- storing the timing offset in a plurality of sync fields in a plurality of servo sectors on the servoing track, wherein the sync fields are radially positioned with about half-track offsets in circumferentially alternating servo sectors to accommodate varying read-write offsets;
- reading back the timing offset stored in the sync fields with the read head;
- and
- synchronizing a write signal of the data pattern on the write track with the timing offset read back from the sync fields.
A method for synchronizing writing in a disk drive, comprising:
- providing the disk drive with a disk having bit patterned media, and a slider with a read head and a write head for reading data from and writing data to the disk, respectively;
- positioning the read head at a read-write offset with respect to the write head;
- writing data with the write head onto a data pattern on a write track of the bit patterned media;
- providing a timing offset between the data pattern on the write track and a data pattern on a servoing track of the bit patterned media with the read head using the data pattern on the servoing track;
- storing the timing offset in a plurality of sync fields in a plurality of servo sectors on the servoing track;
- reading back the timing offset stored in the sync fields with the read head;
- synchronizing a write signal of the data pattern on the write track with the timing offset read back from the sync fields;
- adjusting a clock of the disk drive with the timing offset stored in the sync fields;
- and
- measuring an optimal timing offset by writing at different timing offsets, each incremented by a step between the servo sectors.
Dependencies are inferred from the claim text.