Abstract: Techniques are described for performing a bit-flipping decoding scheme on a G-LDPC codeword. In an example, a decoding system uses two syndrome tables. The first syndrome table identifies a predefined syndrome for a component codeword that protects a bit of the G-LDPC codeword. This predefined syndrome is identified based on a location of the bit and is used to update a current syndrome of the component codeword. The second syndrome table identifies one or more bit error locations for the component codeword. The bit error locations are identified from the second syndrome table based on the current syndrome of the component codeword, as updated. In an example, the error locations are used to update a reliability of the bit if its location corresponds to one of the error locations. A bit flipping decision is made for the bit based on its reliability.

Abstract: A data encoding method, a data decoding method, and a storage controller are provided. The encoding method includes: obtaining a verification data corresponding to a raw data according to a write command; adding the verification data to the raw data, and obtaining a scrambled data accordingly; and performing an encoding operation on the scrambled data to obtain a codeword data. The decoding method includes: performing a decoding operation on a codeword data to obtain a decoded codeword data, and obtaining a pre-scrambling data accordingly; identifying a verification data and a raw data in the pre-scrambling data; identifying one or more first system data corresponding to the raw data according to a read command; and determining whether the raw data is correct by comparing the one or more first system data and the verification data.

Abstract: A BIST engine configured to store a per pattern based fail status during memory BIST run and related processes thereof are provided. The method includes testing a plurality of patterns in at least one memory device and determining which of the plurality of patterns has detected a fail during execution of each pattern. The method further includes storing a per pattern based fail status of each of the detected failed patterns.

Abstract: In some embodiments, an integrated circuit may include a memory self-testing circuit and a memory having a plurality of data storage locations, each location having a unique address. The integrated circuit may further include an output including at least one register capable of storing an address of a memory location where an error has been detected during execution of the memory self-testing circuit. Further, the integrated circuit may include an on-chip clock controller (OCC) circuit including a first output to provide a first clock signal and a second output to provide a second clock signal according to a mode of operation. In a scan mode, the OCC circuit may be configured to enable the first clock signal and the second clock signal and to selectively enable the first clock signal and the second clock signal to be mutually exclusive during a scan capture portion of the scan mode.

Abstract: Embodiments herein discuss tuning a testing apparatus to better match the input response of a target system in which a cable will be used. For example, conductors in the cable may have a different skew depending on the system in which they are used. The testing apparatus may be tuned using frequency information regarding the type of signals that will be driven on the cable when installed in the target system. In one embodiment, the testing apparatus adjusts a testing cycle refresh rate for generating a testing signal which changes the frequency content of the testing signal. Using the adjusted testing cycle refresh rate results in the driver outputting a testing signal that better reflects the actual signals that will be transmitted on the cable in the target system.

Abstract: A memory controller according to an embodiment includes a memory interface that reads out a received word from a non-volatile memory and a decoder that performs bounded distance decoding for the read received word. The decoder sets rm (rm is a natural number equal to or larger than 1) symbols of a plurality of symbols constituting the received word, as options of symbol positions at each of which an error is assumed, generates a test pattern in which m (m is a natural number equal to or larger than 1 and equal to or smaller than the rm) symbols of the rm symbols are objects of rewriting, generates test hard-decision values by rewriting each of hard-decision values of the m symbols that are objects of rewriting in the test pattern, among the symbols, and performs bounded distance decoding for the test hard-decision values.

Abstract: The present disclosure includes apparatuses and methods for physical page, logical page, and codeword correspondence. A number of methods include error coding a number of logical pages of data as a number of codewords and writing the number of codewords to a number of physical pages of memory. The number of logical pages of data can be different than the number of physical pages of memory.

Abstract: Decoding sequentially received vector signaling codewords to obtain sequential sets of data bits, wherein elements of each vector signaling codeword are received in parallel over a plurality of wires, generating an incremental update of a plurality of error correction syndrome values based on each sequential set of data bits according to a check matrix, and upon decoding of a final vector signaling codeword, performing a final incremental update of the plurality of error correction syndrome values and responsively modifying data bits within the sequential sets of data bits by selecting a set of data bits from the sequential sets of data bits according to a symbol position index determined from the plurality of error correction syndrome values, the selected set of data bits altered according to a bit error mask determined from a first error correction syndrome value of the plurality of error correction syndrome values.

Abstract: A computing device includes an interface configured to interface and communicate with a dispersed storage network (DSN), a memory that stores operational instructions, and processing circuitry operably coupled to the interface and to the memory. The processing circuitry is configured to execute the operational instructions to perform various operations and functions. The computing device encrypts data using a key to generate encrypted data and processes it and a password based on a deterministic function to generate transformed data. The computing device masks the key based on a masking function based on the transformed data to generate a masked key, and then combines the encrypted data and the masked key to generate a secure package that is encoded in accordance with dispersed error encoding parameters produce a set of encoded data slices (EDSs) and transmits the set of EDSs to a plurality of storage units (SUs) to be distributedly stored therein.

Abstract: An error correction circuit of a semiconductor memory device including a memory cell array includes an error correction code (ECC) memory that stores an ECC and an ECC engine. The ECC is represented by a generation matrix. The ECC engine generates first parity data based on main data using the ECC, and corrects at least one error bit in the main data read from the memory cell array using the first parity data. The main data includes a plurality of data bits divided into a plurality of sub codeword groups. The ECC includes a plurality of column vectors divided into a plurality of code groups corresponding to the sub codeword groups. The column vectors have elements configured to restrict a location of a sub codeword group in which a mis-corrected bit occurs, in which the mis-corrected bit is generated due to error bits in the main data.

Abstract: Apparatuses, systems, and methods are disclosed for data availability during temporary inaccessibility of a memory region for memory. An apparatus may include a plurality of memory elements and a controller. A controller may be configured to identify a portion of memory of a plurality of memory elements such that data stored in a portion of memory is temporarily inaccessible and other data stored in other portions of memory in the plurality of memory elements is accessible. A controller may be configured to reconstruct data stored in a portion of memory from other data stored in other portions of memory. A controller may be configured to provide reconstructed data while a portion of an array is temporarily inaccessible.

Abstract: Over a period of operation, non-volatile memory can develop a residual resistance that is impractical to remove. For example, in a NAND string of memory cells, trapped charge may build up in a region between the bit lines and drain side select gates, so that even when all the devices of a NAND string are in an “on” state, the NAND string will not conduct. This effect will skew both hard bit data determinations, indicating the data state of a selected memory cell, and soft bit data determinations which may correlate to the reliability of the hard bit data. Techniques are described to factor in such excessive residual resistance when determining the soft bit data.

Abstract: A method for preventing data loss in a RAID includes monitoring storage drives making up a RAID. The method individually tests a storage drive of the RAID by subjecting the storage drive to a stress workload test. This stress workload test may be designed to place additional stress on the storage drive while refraining from adding stress to other storage drives in the RAID. In the event the storage drive fails the stress workload test (e.g., the storage drive cannot adequately handle the additional workload or generates errors in response to the additional workload), the method replaces the storage drive with a spare storage drive and rebuilds the RAID. In certain embodiments, the method tests the storage drive with greater frequency as the age of the storage drive increases. A corresponding system and computer program product are also disclosed.

Abstract: A method for performing low-density parity check (LDPC) decoding includes: in a first decoder which operates in a first mode, performing a plurality of decoding iterations of a codeword using a first algorithm, including: decoding the codeword to generate first information including a number of failed check nodes; linking the number of failed check nodes to a log-likelihood ratio (LLR) value to generate second information; and performing parity check equations for the codeword at check nodes. When a predetermined number of decoding iterations in the first decoder is reached without the parity check equations being solved, decoding of the codeword using the first decoder is stopped, the codeword is input to a second decoder and decoding of the codeword in the second decoder using a second algorithm and the second information is started.

Abstract: A serial arbitration for memory diagnostics and methods thereof are provided. The method includes running a built-in-self-test (BIST) on a plurality of memories in parallel. The method further includes, upon detecting a failing memory of the plurality of memories, triggering arbitration logic to shift data of the failing memory to a chip pad.

Abstract: A low density parity check (LDPC) encoder, an LDPC decoder, and an LDPC encoding method are disclosed. The LDPC encoder includes first memory, second memory, and a processor. The first memory stores an LDPC codeword having a length of 16200 and a code rate of 4/15. The second memory is initialized to 0. The processor generates the LDPC codeword corresponding to information bits by performing accumulation with respect to the second memory using a sequence corresponding to a parity check matrix (PCM).

Abstract: 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.

Abstract: The disclosed computer-implemented method for distributing information across distributed storage devices may include (1) dividing, at a computing device, each of “K” distributed storage devices (DSDs) in a plurality of DSDs into “P” portions, where “P” is a sum of “M” data portions and “N” parity portions, (2) creating “K” erasure-coded volumes, where each volume includes one portion on different DSDs, “M” data portions, and “N” parity portions, and (3) combining the “K” volumes to create a file system. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: A data storage device is disclosed comprising a non-volatile storage medium (NVSM), wherein a plurality of codewords and corresponding parity sector are written to the NVSM and then read from the NVSM. Each codeword read from the NVSM is processed using a Viterbi-type detector, thereby generating codeword reliability metrics. The codeword reliability metrics for at least some of the codewords are processed using a low density parity check (LDPC) type decoder, thereby generating a LDPC reliability metric for each symbol of at least one codeword. The LDPC reliability metrics for at least one of an un-converged codeword are processed using the parity sector, thereby updating the un-converged codeword reliability metrics. Processing the codeword reliability metrics with the LDPC decoder and updating the reliability metrics with the parity sector is repeated at least once before updating the LDPC reliability metrics of at least the un-converged codeword using the Viterbi-type detector.

Abstract: Log likelihood ratio (LLR) values that are computed in a flash memory controller during read retries change over time as the number of program-and-erase cycles (PECs) that the flash memory die has been subjected to increases. Therefore, in cases where an LLR table is used to provide pre-defined, fixed LLR values to the error-correcting code (ECC) decoding logic of the controller, decoding success and the resulting BER will degrade over time as the number of PECs to which the die has been subjected increases. In accordance with embodiments, a storage system, a flash memory controller for use in the storage system and method are provided that periodically measure the LLR values and update the LLR table with new LLR values. Periodically measuring the LLR values and updating the LLR table with new LLR values ensures high decoding success and a low BER over the life of the flash memory die.