Seagate Technology Incorporated

EweChye Tan

Jonathan Williams Haines

Samir Mittal

Todd David Baumann

Justin Won

A method and apparatus associated with circuitry configured to perform a selected one of a plurality of different data integrity operations on stored data in relation to a manner in which the data are to be retrieved. In some embodiments a data storage device is partitioned into a plurality of partitions, and one of a plurality of different data integrity operations is performed on stored data in relation to which partition of the plurality of partitions the stored data is in.

Storage system with alterable background behaviors

A method and apparatus for reducing the effects of non-repeatable runout (NRRO) in the estimation of repeatable runout (RRO) in a disc drive is disclosed. PES information is a acquired in a way that leads to randomization of the phase of the NRRO, thereby decreasing the number of revolutions required to estimate the true RRO. A number of RRO estimation measurements are taken over a number of non-consecutive disc revolutions that are spaced in time. In one embodiment, one revolution of RRO data is collected from each head before collecting a second revolution of RRO data from any of the heads. In another embodiment, RRO estimation is concurrent with media certification, such that PES data is obtained while the head is in the write position and writes a track of data for media certification. Similarly, PES data for the read position is obtained while concurrently reading back the written data.

Interleaved repeatable runout estimation

The present invention is a method of correcting radial position error signal (PES) values by utilizing predetermined error correction values located at predetermined locations in advance of their associated servo fields. Calculated correction values are written to zero-acceleration path (ZAP) fields on the disc during the manufacture process. ZAP fields are positioned before the servo fields whose PES they are designed to correct. The ZAP field is comprised of two or more correction data elements to correct subsequent PES values. As the read/write head flies along a track, it reads a ZAP field, and stores the PES correction data in local random access memory (RAM). Subsequently, the corresponding servo field is read and the stored PES correction data is used to correct the PES. Two types of ZAP fields are written on the disc&mdash;one type for read operations, another type for write operations. An arrangement of ZAP fields relative to servo and data track nulls allows for the read head to gather the ZAP field information in the write position, without having to move from the write position to the read position and back to the write position in the middle of a write operation.

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Longmont, CO, United States of America

EweChye Tan