One or more detectors detect data from respective one or more analog sources operable to read from a storage medium. A buffer pool is between the decoders and two or more detectors. The decoders are simultaneously operable, via the buffer pool, to independently decode the data from the one or more detectors.

According to one embodiment, a storage device includes a detector, a demodulator, a controller, and a recorder. When a user data item is split data including first data being at least part of a first code word and second data being at least part of a second code word, the controller sets a start position of the second data for forced search of the second code word on the basis of the position of a sync mark recorded in the recorder when the forced search of the first code word has succeeded.

A storage device includes a recording medium, a first memory storing first data read from the recording medium, and a controller. The controller searches for read target data in the first data by executing a parity check on second data that is in the first data and starts at a first position, while executing the parity check, determining whether or not an interruption condition is satisfied, storing the second data in a second memory when the parity check completes without the interruption condition being satisfied and a result of a completed parity check satisfies a first condition, and executing a parity check on third data that is in the first data and starts at a second position, responsive to the interruption condition being satisfied and responsive to the result of the completed parity check not satisfying the first condition.

According to one embodiment, a magnetic disk device includes a read control system that extracts scrambled data from media data read from a medium and inspection data associated with a seed value at the time of write, generates inspection data for data extracted from the media data, obtains from the inspection data and inspection data extracted from the media data, a seed value associated with both, compares this seed value with the seed value expected by the controller, and evaluates, when the comparison result is a mismatch, the data as an error, whereas when match, descrambles the data extracted from the media data using the seed value.

According to the embodiment, an HDC receives a plurality of data segments from a host, and executes generation and addition of a first code and output of a data segment to which the first code is added to each data segment. An HDC calculates exclusive OR with respect to the first codes, and outputs obtained first information. The RWC performs data conversion and calculation of exclusive OR on the plurality of data segments to which the first code is added, and outputs the plurality of data segments after the data conversion and a track parity obtained by the calculation of the exclusive OR. The RWC acquires the first code from the plurality of data segments. The RWC calculates exclusive OR with respect to a group of the second codes which are the acquired first codes to acquire second information. The RWC compares the first information with the second information.

According to the embodiment, an HDC receives a plurality of data segments from a host, and executes generation and addition of a first code and output of a data segment to which the first code is added to each data segment. An HDC calculates exclusive OR with respect to the first codes, and outputs obtained first information. The RWC performs data conversion and calculation of exclusive OR on the plurality of data segments to which the first code is added, and outputs the plurality of data segments after the data conversion and a track parity obtained by the calculation of the exclusive OR. The RWC acquires the first code from the plurality of data segments. The RWC calculates exclusive OR with respect to a group of the second codes which are the acquired first codes to acquire second information. The RWC compares the first information with the second information.

According to one embodiment, a magnetic disk device includes a read control system that extracts scrambled data from media data read from a medium and inspection data associated with a seed value at the time of write, generates inspection data for data extracted from the media data, obtains from the inspection data and inspection data extracted from the media data, a seed value associated with both, compares this seed value with the seed value expected by the controller, and evaluates, when the comparison result is a mismatch, the data as an error, whereas when match, descrambles the data extracted from the media data using the seed value.

An apparatus includes a memory and a controller. The memory may be configured to store data. The controller may be configured to process a plurality of read/write operations to/from the memory, receive a codeword from the memory, generate a plurality of syndromes of the codeword at a plurality of possible code rates, generate a plurality of count values by counting a number of unsatisfied parity checks in each of the plurality of syndromes, generate a plurality of normalized values by dividing the plurality of count values by a plurality of lengths of the plurality of possible code rates respectively, and determine a bit error rate value of the memory based on a lowest value among the plurality of normalized values.

Embodiments are related to systems and methods for data processing, and more particularly to systems and methods for multiple codeword processing in a data processing system. An illustrative data processing system includes a processing circuit that processes unprocessed codewords, and provides failed codewords when the processing fails to converge. The system may further include an input buffer circuit that selectively stores a combination of at least one of the unprocessed codewords and at least one of the failed codewords. The input buffer circuit includes a first portion that maintains any of the unprocessed codewords and the failed codewords, and a second portion that maintains only the failed codewords.

Embodiments of the present inventions are related to systems and methods for data processing, and more particularly to systems and methods for recovering data where synchronization information is not detected.