Abstract: A coding system for digital data includes a constrained encoder module that generates encoded data based on a first constrained code, a bit insertion module that inserts at least one bit location in the encoded data, an error correcting code (ECC) encoder module that generates ECC parity bits based on the at least one bit location and the encoded data, and an inner encoding module that generates inner-code parity bits based on the encoded data and programs the inner-code parity bits into the at least one bit location.

Abstract: A system and method for data storage by shredding and deshredding of the data allows for various combinations of processing of the data to provide various resultant storage of the data. Data storage and retrieval functions include various combinations of data redundancy generation, data compression and decompression, data encryption and decryption, and data integrity by signature generation and verification. Data shredding is performed by shredders and data deshredding is performed by deshredders that have some implementations that allocate processing internally in the shredder and deshredder either in parallel to multiple processors or sequentially to a single processor. Other implementations use multiple processing through multi-level shredders and deshredders. Redundancy generation includes implementations using non-systematic encoding, systematic encoding, or a hybrid combination.

Abstract: A test apparatus is provided for testing memory under test which stores a data string including an error correction code in the form of additional data. The test apparatus comprises: a logic comparator which compares each of the data sets included in a data string read out from the memory under test with a corresponding anticipated value created beforehand; a data error count unit which counts the number of data sets that do not match the respective anticipated values; and a defect detection unit which provides a function whereby, in a case that the count value counted by the error count unit exceeds a predetermined upper limit number which is equal to or greater than 1, determination is made that the memory under test is defective.

Abstract: Among other disclosed subject matter, a magnetic disk controller can include an index detecting unit to detect an index of the magnetic disk, an error check code generating unit to, after the index detecting unit detects the index, generate a first error check code for first write data based on the first write data and a first physical address of a first sector subsequent to the detected index, and a writing control unit to cause the first error check code generated by the error check code generating unit, the first write data and the first physical address to be written into a second sector subsequent to the first sector.

Abstract: An information recording medium to which data extra ECC is applied, and a method and apparatus for managing the information storage medium is provided. The method includes: determining whether extra ECC is applied with respect to data that is to be recorded on the information recording medium, and deciding an extra ECC application rate; assigning an area for recording a data block including an extra parity generated by applying the extra ECC to the data that is to be recorded on the information recording medium, to the information recording medium; assigning an extra ECC management information area for recording extra ECC management information for managing the extra ECC, to the information recording medium; and recording or updating the extra ECC management information in the extra ECC management information area. Therefore, it is possible to improve reproduction reliability while maintaining reproduction compatibility with conventional apparatuses.

Abstract: A data modulation method and a data error correction method are provided. The data modulation method includes generating a channel sequence for an input sequence, determining whether or not the channel sequence violates a Run Length Limit (RLL) constraint, and performing, when the channel sequence violates the RLL constraint, bit flip at a position prior to a position at which the RLL constraint is violated among positions of bits included in the channel sequence. The data error correction method includes detecting an error bit of received data using a parity check matrix, determining whether or not the error bit is an error caused by bit flip, and correcting the error bit when the error bit is an error caused by bit flip for applying an RLL constraint.

Abstract: A method for adaptively applying an error-correcting code to a storage device is disclosed. A determination is made that a system is in an idle state of input/output requests. First data symbols are copied into a first location within a buffer. First data symbol errors corrected using a first error-correcting code. Second data symbols including corrected bits are written in a second location on the recording media with a second error-correcting code. An error number for the second data symbols in the second location is determined. If the error number is below a first threshold error number, the first data symbols are deleted. If the error number is above the first threshold error number, the second data symbols are deleted.

Abstract: First data representing user data and third data use the same error correction codes. The first data has a first error correction block structure and the third data has a second error correction block structure. That is to say, the first data and the third data have their respective error correction block structures proper for them. In particular, the recording density of the third data is made less dense than the recording density of the first data, and the number of correction codes in the first error-correction block is set at a multiple of m whereas the number of correction codes in the second error-correction block is set at n/m times the number of correction codes in the first error-correction block so that a data-piece count in the second error-correction block is also n/m times a data-piece count in the first error-correction block. As a result, it is possible to provide a good technique of recording shipping-time information onto a high-recording-density disc.

Abstract: In order to correct an error in input data to thereby obtain write data, in a memory core, an EXOR element performs arithmetic processing based on an output result of an output data latch for latching read data and a result of inputted array input data, and a selector selects a result of the arithmetic processing to prepare write data. Thus, data obtained after performance of the arithmetic processing can be generated in a semiconductor memory by an operation performed immediately after data read. In addition, it is unnecessary to transfer data to an external logic circuit. Therefore, the result of the arithmetic processing can be written to a memory cell block in a subsequent clock.

Abstract: The application discloses storage circuitry with a pulse generator used to control switches on two inputs to the storage circuitry thereby connecting either operational data or diagnostic data to the storage circuitry. Thus, the pulse generator selects the data paths by outputting pulses to a diagnostic output or to a functional output, and these pulses controlling the switches on the two inputs to the storage circuitry.

Abstract: A DSP of a DVD recorder includes: a gain setting portion determining appropriate values of a first gain ? and a second gain ? when playback of an optical disc is performed, recording the first gain ? and the second gain ? thus determined in a gain storing portion, and setting them in a main differential amplifier and a sub differential amplifier, respectively; and a correction performing portion reading, when recording on the optical disc is performed, the first gain ? and the second gain ? stored in the gain storing portion, correcting at least one of them, and setting them in the main differential amplifier and the sub differential amplifier, respectively.

Abstract: A hard disk drive with a disk that has a plurality of data bits. The drive includes a circuit that reads each data bit n times and selects a value for the bit based on a reliability factor. The circuit may select a bit based at least in part on the most frequent occurrence of one of a plurality of values. For example, if more 0s occurred than 1s the bit would be set to 0. The reliability factor may be a ratio of the occurrence of 0s to the occurrence of 1s. A bit can be not selected or deselected if the reliability factor exceeds a threshold value.

Abstract: Four ECC blocks are recorded in a burst cutting area of an optical disc. Each ECC block is constituted by a BCA content code of 1 byte, content data length of 1 byte, and content data of 14 bytes. Of the BCA content data, the leading 6 bits are used for application ID and the remaining 2 bits are used for block number. Disc ID is stored in the content data. Since the four ECC blocks exist, the optical disc can be managed individually by four applications at the maximum. Thus it becomes possible to manage the same optical disc by a plurality of applications.

Abstract: A method is provided of data storage by encoding a bit stream on a surface. The method involves printing coded data on the surface which encodes the bit stream, and printing alignment data on the surface which is indicative of a position of the coded data on the surface. The alignment data has a first registration structure indicative of a plurality of reference points indicative of a position of the coded data in an alignment direction, and a second registration structure indicative of a plurality of reference points indicative of a position of the coded data in a direction perpendicular to the alignment direction.

Abstract: A method and device for error analysis particularly adoptable for a recording medium such as an optical disc are disclosed. The present invention executes an encoding-like operation such as an interleaving operation to error flags during reproducing data from the optical disc, so as to obtain number and distribution of the errors on the disc.

Abstract: A recording and/or reproducing method, a recording and/or reproducing apparatus, and a computer readable recording medium storing a program for performing the method. A recording unit block in which invalid data is partially padded is written on an information storage medium along with padding information indicating that the invalid data is included in the recording unit block. The padding information is useful in determining whether the recording unit block includes the padding data. Accordingly, unnecessary retrial processes of a drive system are reduced such that the performance of the drive system is improved and error correction capability is enhanced.

Abstract: A disk drive is disclosed comprising a disk having a plurality of data tracks, wherein each data track comprises a plurality of data sectors. A head is actuated radially over the disk in order to read one of the data sectors from a target data track on the disk. The data sector is stored in a buffer and decoded with an error correction code (ECC) decoder. When the decode fails, an erasure window is adjusted based on a number of non-read data sectors recorded in the target data track, wherein the erasure window comprises a length spanning at least one ECC symbol in the data sector. The data sector is read from the buffer and decoded with the ECC decoder using the erasure window.

Abstract: A system includes a host first-in first-out (FIFO) module, a first encoder module, a control module, a disk FIFO module, and a second encoder module. The host FIFO module receives a block having data and selectively receives a host logical block address (HLBA). The first encoder module generates a first checksum based on the data and the HLBA and generates a first encoded block. The control module appends the HLBA to the first encoded block and generates an appended block. The disk FIFO module receives the block from the host FIFO module. The second encoder module selectively generates a second checksum based on the HLBA and the data in the block received by the disk FIFO module. The second encoder module compares the block received by the disk FIFO module to the block received by the host FIFO module based on the first and second checksums.

Abstract: A system includes a receive module, a control module and a read module. The receive module receives a first block that includes first data, a first cyclic redundancy check (CRC) checksum, and a first error-correcting code (ECC) value. The first CRC checksum and the first ECC value include a logical block address (LBA). The control module generates a first derived CRC checksum based on the first data. The first derived CRC checksum does not include the LBA. The read module reads a second block from a parity disk. The second block includes parity data, a second CRC checksum, and a second ECC value. The second CRC checksum and the second ECC value include the LBA.

Abstract: An interpretive script language that provides an abstraction layer between redundant array of independent disks (RAID) algorithms and RAID hardware architecture. The interpretive script language provides greater flexibility and performance over conventional RAID processors. The interpretive script language may be used with any RAID hardware architecture, is not dependent on a specific RAID algorithm, and enables efficient communication to a RAID processor from any entity that desires RAID services. The entity requesting RAID services sends a command to a RAID processor, which includes pointers to a script entry point for scripts stored in a table memory in the RAID processor, and pointers to the data and parity (for example, in a buffer memory) on which to perform exclusive OR (XOR) operations.

Abstract: A recording medium on which a recording/reproducing unit block is recorded, an apparatus to record and/or reproduce data on/from the recording medium, and a method of recording/reproducing the data on/from the recording medium. The recording/reproducing unit block comprises invalid data used in disc certification, and an identifier to indicate that the invalid data is included in the recording/reproducing unit block, the invalid data being used during the disc certification on a portion of the recording medium or the entire recording medium.

Abstract: Various embodiments of the present invention provide systems and methods for deriving data from a defective media region. As an example, a method for deriving data from a defective media region is disclosed that includes providing a storage medium and performing a media defect detection that indicates a defective region on the storage medium. A first data decode is performed on data corresponding to the defective region. The first data decode yields a first output. It is determined that the first output failed to converge and based at least in part on the failure of the first output to converge, a second data decode is performed on the data corresponding to the defective region. The second data decode includes zeroing out any soft data corresponding to the defective region and providing a second output.

Abstract: Improved memory devices, circuitry, and data methods are described that facilitate the detection and correction of data in memory systems or devices by increasing the data area of user data being covered by the ECC code. This averages any possible bit errors over a larger data area and allows a greater number of errors to be corrected by a combining the ECC codes in the coverage area without substantially changing the overall size of ECC codes being stored over a single sector approach. In one embodiment of the present invention, the size of the data block utilized for ECC coverage is variable and can be selected such that differing areas of the memory array or data types can have a differing ECC data coverage sizes. It is also noted that the ECC algorithm, math base or encoding scheme can also be varied between these differing areas of the memory array.

Abstract: A method of controlling a RAID system including a plurality of disk devices is provided. The method allows for reading data recorded onto an area adjacent to an area where a write error occurs when the write error is detected while data is written into the disk device. When an error is detected from the data read from the adjacent area, the data recorded onto the adjacent area is restored by using a RAID function and the restored data is written into the adjacent area.

Abstract: An error correction device is provided. The error correction device includes a code storage unit where a plurality of error correction codes are stored, a first error correction unit to correct a data error detected from input data by using one of a plurality of error correction codes and to output correction data, a buffer to store the correction data, and a second error correction unit to generate a new correction code from the correction data, to compare another of a plurality of error correction codes with the new correction code and to output a comparison result.

Abstract: An error correction device is provided. When an error of a data group stored in a dynamic random access memory (DRAM) device is detected, a memory controller of the error correction device executes a burst read and write, burst write or burst read-modify-write (RMW) operations to the DRAM instead of the conventional single read-modify-write (RMW) operation, thereby reducing the occupied bandwidth of the DRAM.

Abstract: Error correction in a disk drive is performed by error correction circuitry which accepts data read from a data storage medium. The error correction circuitry performs both block error correction in a first data domain and sector error correction in a second data domain. A sector FIFO buffer is used to facilitate the error correction in real time, or “on-the-fly.” The sector FIFO buffer also enables conversion of the corrected data to the first data domain. The error correction circuitry also generates an ECC block comprising a plurality of sectors and writes the ECC block. The circuitry generates a tag prior to writing the ECC block and adds the tag to each of a plurality of sectors. During a read operation, the circuitry detects a write disruption when the tags for all of the plurality of sectors in the ECC block are not identical.

Abstract: A magnetic disk control apparatus includes an error determining unit and a correcting unit. When a correctable read error has occurred during read access to a disk drive, the error determining unit specifies an area on the disk drive where an error may occur due to the same cause as that of the correctable read error. The correcting unit corrects the area specified by the error determining unit by rewriting the area.

Abstract: A system and method for correcting errors in an ECC block using soft-decision data. In an embodiment, a soft-decision ECC decoding method, uses “soft” data indicative of how reliable bits of data are when read out. Such a method may use an update module for receiving and manipulating the soft-decision data and iteratively change bits or groups of bits based upon an ordering of the reliability factors. Then a calculator module may determine the total number of errors still remaining after each iteration. Determining just the total number of errors instead of the actual locations is far less computationally intensive, and therefore, many combination of potential flip-bit combination may be analyzed quickly to determine if any combination might reduce the total number of errors enough to be handled by the conventional hard-decision ECC decoding method.

Abstract: Memory devices, circuitry, and data methods are described that facilitate the detection and correction of data in memory controllers, memory systems, and/or non-volatile memory devices by allowing the number of ECC check bytes being utilized to be varied to increase or decrease the ECC check depth. This allows the depth of the ECC coverage (the overall number of bit errors detectable and/or correctable in each sector by the stored ECC check bytes) to be selected based on the application, the amount of available data storage for ECC check bytes in the overhead/spare area associated with the sector, the version of memory device or controller being utilized, or the number of errors being seen in the memory system, device, bank, erase block, or sector (the error incidence rate), while the base data size of the area (sector) covered by the ECC check bytes stays the same.

Abstract: A storage apparatus composed of a plurality of magnetic disk devices are provided. An encoding unit generates, after dividing original data, a plurality pieces of encoded data equal to or more than the number of division by use of a code of which redundancy is variable. A redundancy control unit varies the redundancy in the encoding unit in accordance with the importance of the original data. A distribution processing unit distributes and stores the plurality of encoded data to and in the plurality of magnetic disk devices. A decoding unit retrieves the encoded data corresponding to, at least, the division number of the original data from the magnetic disk devices so as to decode the original data.

Abstract: A recording and/or reproducing method, a recording and/or reproducing apparatus, and a computer readable recording medium storing a program for performing the method. A recording unit block in which invalid data is partially padded is written on an information storage medium along with padding information indicating that the invalid data is included in the recording unit block. The padding information is useful in determining whether the recording unit block includes the padding data. Accordingly, unnecessary retrial processes of a drive system are reduced such that the performance of the drive system is improved and error correction capability is enhanced.

Abstract: The present invention provides an error correction method and apparatus, and also an optical disc playback method and apparatus. The error correction method in the present invention is used to perform error correction on data read from an optical disc, comprising: obtaining the error detection information of a block corresponding to the read data; determining data error type in a data stream unit derived from the block according the error detection information; according to the data error type and predefined reference error type, judging whether to reserve the data stream unit for optical disc playback. By using the error detection information of the block which is decarded by using the existing technologies, the player can perform further error correction to try to avoid data errors which may produce interruption during optical disc playback.

Abstract: A reproduction apparatus includes a reproduction unit reading a reproduced signal of the data recorded on an optical disk, a reproduced signal processing unit performing ECC decoding for the reproduced signal using a predetermined parameter value, a storage unit storing the parameter number associated with the currently set parameter value and a parameter table listing parameter values and associated parameter numbers, and a control unit controlling the reproduction unit and the reproduced signal processing unit. The control unit, when ECC decoding fails, changes the parameter values in the order of the parameter numbers and controls the reproduced signal processing unit until ECC decoding succeeds in retried reproduction processing and, when ECC decoding succeeds, stores the parameter number associated with the currently set parameter value and sets in the next retried reproduction processing the parameter value associated with the stored parameter number in the reproduced signal processing unit.

Abstract: A method applied to an optical disc drive for calculating an error detection code corresponding to a data sector is disclosed. The data sector includes a plurality of bytes arranged in a matrix having N lines along a first direction and M lines along a second direction perpendicular to the first direction. The method includes: along the first direction, calculating error detection codes corresponding to M bytes located at each of the N lines, wherein for each of the N lines, only bytes having error bits affect an error detection code for the line; adjusting an error detection code of each of the N lines according to a displacement between each of the N lines and a last line of the N lines; and then determining the error detection code of the data sector by summing up the displacement-adjusted error detection code of each of the N lines.

Abstract: Apparatuses and methods for defect replacement when an optical storage medium is read are provided. When the defect management is LOW, a pick-up head retrieves a set of data from the optical storage medium; a defect detector detects whether there is a defect in the set; if yes, a processor determines whether a replacement for the defect is in the set; and if yes, an interface transmits the replacement from the set.

Abstract: A method for decoding data stored in a disk is achieved by demodulating a physical cluster read out from the disk and outputting LDC (long distance code) data and BIS (burst indicator subcode) data included in the physical cluster, temporarily storing part of the LDC data and BIS data of the data included in the physical cluster in a first memory portion, reading out the LDC data and BIS data stored in the first memory portion and storing the read out data in a second memory portion, reading out LDC data and BIS data requiring error correction from the second memory portion and temporarily storing the read out data in the first memory portion, and storing LDC data and BIS data for which data processing operation including the error correction operation is completed in the second memory portion.

Abstract: An ECC block is constituted by RS(248, 216, 33). Of a data length of 216 bytes (symbols), only 16 bytes are allocated to BCA data and the remaining 200 bytes are used for fixed data having a predetermined value. Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities of 32 bytes (symbols) are calculated. Only the BCA data of 16 bytes and the parities of the former 16 bytes of the 32-byte parities, that is, a total of 32 bytes only, are recorded in a burst cutting area of an optical disc. In decoding, error correction processing is carried out by using the fixed data of 200 bytes. The unrecorded parities of 16 bytes are processed as having been erased. Thus, the error correction capability in a burst cutting area of an optical disc can be improved.

Abstract: A method and apparatus for providing a read channel having combined parity and non-parity post processing is disclosed. A post-processor combines parity and non-parity post processing to make both parity and non-parity corrections so that error events that cannot be detected by parity may be corrected. Non-parity detectable error events are only kept for consideration if their likelihood is above a set threshold.

Abstract: An architecture and method for executing write commands in a storage array is disclosed. The data strips of the data stripes of the storage array each include a parity check bit. The parity strip of each stripe includes a plurality of parity check bits, each of which is uniquely associated with one of the data strips of the stripes. The inclusion within each data stripe of parity bits associated with each data strip and the party strip provides a method for identifying a corrupted or degraded data condition that occurs as a result of a server failing fails during a write command.

Abstract: An efficient method to apply an erasure encoding and decoding scheme across dispersed data stores that receive constant updates. A data store is a persistent memory for storing a data block. Such data stores include, without limitation, a group of disks, a group of disk arrays, or the like. An encoding process applies a sequencing method to assign a sequence number to each data and checksum block as they are modified and updated onto their data stores. The method preferably uses the sequence number to identify data set consistency. The sequencing method allows for self-healing of each individual data store, and it maintains data consistency and correctness within a data block and among a group of data blocks. The inventive technique can be applied on many forms of distributed persistent data stores to provide failure resiliency and to maintain data consistency and correctness.

Abstract: Apparatuses and methods for utilizing error correction code in a data buffer or data storage device. In one variation, a single memory device is utilized to store both the data and the associated error correction code. The data and the associate error correction codes are stored on separate memory banks on the memory device. The error correction code may be consolidated into one or more regions on the memory device to improve the utilization of the available memory space on the memory device. In addition, by utilizing separate memory banks to store the data and the associated error correction code, the data and the error correction code can be accessed in an overlapping manner.

Abstract: A system for decoding coded data printed in ink on a surface. The coded data includes an encoded bit stream and associated redundancy data, and a registration structure of clock tracks indicative of a position of the coded data in the direction perpendicular to an alignment direction and two alignment lines for each clock track. The system has a store for storing the coded data and a decoder for determining a codeword format for the coded data, reading the coded data from the store using the determined format, correcting errors in the encoded bit stream, and writing the corrected data to the store. The coded data is read so as to de-interleave the encoded bit stream and redundancy data into codewords. The decoder uses an alignment phase-locked loop (PLL) to determine a position of the alignment lines so as to determine the position of each respective track and update the alignment PLL.

Abstract: A method for an error recovery process in a disk-drive device. The method includes starting the error recovery process in response to an error which has occurred in a process corresponding to a command from a host to access a disk. The method also includes receiving a new read command from the host during the error recovery process. In addition, the method includes interrupting the error recovery process in accordance with preset conditions and reading out data from the disk at an address designated by the read command. Furthermore, the method includes transferring the read-out data to the host.

Abstract: A method for automatically calibrating intra-cycle timing relationships between command signals, data signals, and sampling signals for an integrated circuit device. The method includes generating command signals for accessing an integrated circuit component, accessing data signals for conveying data for the integrated circuit component, and accessing sampling signals for controlling the sampling of the data signals. A phase relationship between the command signals, the data signals, and the sampling signals is automatically adjusted to calibrate operation of the integrated circuit device.

Abstract: The recording apparatus adds EDC to user data and transfers the EDC-added data to the scrambler in a sequence different from the coding direction Q. Though the processing data is added at an end in the direction Q, it is inserted at middle in the different sequence. Therefore, in order to transfer the EDC-added data in the different sequence, the EDC generator calculates an EDC intermediate value from an expected value of a latter part of an even number sector. Then, the EDC generator receives the user data in the different sequence and calculates EDC from expected values of the first half of the even number sector and an odd number sector and the EDC intermediate value. The expected value is an error detecting value of code string that has the same number of bits as the EDC-added data and a corresponding bit in the sequence of the direction Q is 1 and other bits are 0.

Abstract: A system and method for data storage by shredding and deshredding of the data allows for various combinations of processing of the data to provide various resultant storage of the data. Data storage and retrieval functions include various combinations of data redundancy generation, data compression and decompression, data encryption and decryption, and data integrity by signature generation and verification. Data shredding is performed by shredders and data deshredding is performed by deshredders that have some implementations that allocate processing internally in the shredder and deshredder either in parallel to multiple processors or sequentially to a single processor. Other implementations use multiple processing through multi-level shredders and deshredders. Redundancy generation includes implementations using non-systematic encoding, systematic encoding, or a hybrid combination.

Abstract: A method of a method of replacing bad sectors in a Hard Disk Drive comprises detecting bad sectors on the Hard Disk Drive; remapping the bad sectors to an auxiliary data storage device comprising an Magnetoresistive Random Access Memory connected to the Hard Disk Drive; and storing data on the auxiliary storage device.

Abstract: In an error correction method, an error correction of data can be completed readily in a short period of time. In this method, actual data are written together with additional data to a magnetic disk having sectors. The actual data have a first length. The additional data are produced from source data. The source data are formed by predetermined data or the actual data. The sectors of the magnetic disk have a read/write unit of a second length that is longer than the first length. One of the sectors to which actual data to be read have been written is specified, and actual data and additional data are read from the specified sector. The read additional data are verified with the source data. A first error correction is performed on the read additional data based on a result of the verification.

Abstract: An error correcting apparatus includes a storing means for storing product code with n2 rows and n1 columns, an error correcting unit 5 that performs error correction for four code sequences simultaneously in parallel, and a bus control unit 2 for reading codes on four rows from the buffer memory 1 and transferring the codes to the error correcting unit 5. The bus control unit 2 reads and transfers four consecutive codes on each of four rows in order before shifting the reading position by four codes in the row direction.