According to an embodiment, the magnetic disk device includes a disk medium and a control circuit. The disk medium includes a first region including a first track. The control circuit controls a write operation of first data to the first track, executes error correction coding of the first data during the write operation. The control circuit makes first determination on whether the written first data is protected by an error correction code. The control circuit sets a second track in a location adjacent to the first track in accordance with a result of the first determination.

A memory system and method of operating the same is described, where the memory system is used to store data in a RAIDed manner. The stored data may be retrieved, including the parity data so that the stored data is recovered when the first of either the stored data without the parity data, or the stored data from all but one memory module and the parity data, has been received. The writing of data, for low write data loads, is managed such that only one of the memory modules of a RAID stripe is being written to, or erased, during a time interval.

The present disclosure describes aspects of codeword interleaving for magnetic storage media. In some aspects, segments of a codeword are spread or interleaved across multiple sectors of magnetic storage media. Data for one or more codewords may be received by a read channel and, for each codeword, a respective indicator is selected or received. The indicator may indicate which partitions of the multiple sectors that segments of one of the codewords are to be written. The data is then encoded to provide the codewords and segments of the codewords are placed in an interleaver based on the respective indicator corresponding to the codeword. The codeword segments are written from the interleaver to partitions of the multiple sectors of the magnetic storage media. By so doing, codewords may be spread across multiple sectors, such that a loss of a few sectors does not prevent readback and decoding of the codewords.

An error correction code (ECC) encoder includes a plurality of exclusive OR (XOR) gates configured to receive a k-bit original data in parallel and configured to perform a plurality of XOR operations to the k-bit original data to output a (nk)-bit parity data. The k-bit original data and the (nk)-bit parity data form an n-bit codeword, k denotes a natural number and n denotes a natural number which is greater than k.

A disk device includes a disk medium, a magnetic recording head, a processor configured to control the magnetic recording head to write data to and read data from a plurality of tracks of the disk medium on a sector-by-sector basis, and a check value generation circuit configured to generate, for each of the plurality of tracks, check value data based on data stored in one or more sectors of the track. The processor controls the magnetic recording head to write check value data for a first track of the plurality of tracks in a first sector on the disk medium and check value data for a second track of the plurality of tracks in a second sector on the disk medium that is adjacent to the first sector.

A method includes writing first data to a first track of a magnetic recording medium of a storage device. First parity sectors corresponding to the first data are written. The first parity sectors have a first size. Second parity sectors corresponding to the first data are written. The second parity sectors have a second size. Second data is written to a second track of the magnetic recording medium. The second track is adjacent to the first track. It is determined whether an unrecoverable data error has occurred on the second track. After writing to the second track and determining that no unrecoverable data error has occurred, the first and second parity sectors corresponding to the first data are released.

A data storage device is disclosed comprising a head actuated over a disk. A first plurality of codewords and corresponding parity sector are generated, and a second plurality of codewords and corresponding parity sector are generated. The first and second plurality of codewords are written to the disk, and during a read of the first and second set of codewords, M codeword locations within the data track that are unrecoverable are saved, and N codeword locations out of the M codeword locations are selected based on a quality metric of the read. The N codewords are reread from the data track at the N codeword locations and reliability metrics associated with the N codewords are saved. The saved reliability metrics are updated using at least one of the first parity sector or the second parity sector.

A magazine-based data storage library in connection with a disk drive-based archive storage system is described that essentially generates parity data for tape formatted data streams (stored to tape cartridges) that do not align by way of data blocks or file marks. Data streams intended for tape storage sent to tape cartridges are also sent to a disk drive storage system via an encoder where parity of the data streams can be generated. More specifically, the encoder digitally formats tape blocks and tape marks (as well as other tape formatted structure) in a digital stream of data that can be added to other encoded digital streams of data to generate parity. To reconstruct a specific tape cartridge from a tape set, the encoded data from each of the tapes in the tape set are subtracted from the parity data and the remaining encoded data is decoded and sent to a designated tape cartridge.

Techniques for receiving data at a physical coding sublayer (PCS) transmit structure from a media access control (MAC) sublayer are provided. A PCS transmit structure is configured to receive data from a MAC sublayer, the PCS transmit structure comprising a first FEC hardware module that performs FEC encoding, in a first clock domain, on the data to generate FEC encoded data. Further, a PCS receive structure configured to receive the FEC encoded data from the PCS transmit structure, the PCS receive structure comprising a second FEC hardware module is configured to perform FEC decoding, in the second clock domain, on the FEC encoded data to generate FEC decoded data.

In an information recording device, when receiving an erase command by a receiver, a controller erases data of an erased area by overwriting data in an information area, to corrupt the data in the information area, using an erasing pattern. The erased area is specified by an erase start position and a size of the data to be erased on the optical disc. The data in the information area is arranged as partial data in a series of data arranged in a direction of internal parity of error correction so that correction is disabled in both of a correction processing by the internal parity of the error correction and a correction processing by external parity of the error correction when the data in the information area is overwritten using the erasing pattern.