Abstract: A memory system includes a non-volatile memory and a controller. The controller is configured to perform an error correction on data read from a memory region of the non-volatile memory, and set a value of a parameter corresponding to a number of parity bits to be added to write data to be written into the memory region based on a number of data bits corrected in the error correction of the read data in a case where the error correction is successful.

Abstract: According to one embodiment, a semiconductor memory device includes first and second memory cells, first and second word lines, and a bit line. The first and second memory cells are coupled to each other and adjacent to each other. When a state of the second memory cell is the first state or one of the states corresponding to a lower threshold voltage distribution than that of the first state, the first memory cell data is read in a first period during which a first voltage is applied to the second word line. And when the state of the second memory cell is the second state or one of the states corresponding to a higher threshold voltage distribution than the second state, the first memory cell data is read in a second period during which a second voltage higher than the first voltage is applied to the second word line.

Abstract: A memory controller including: a fault determination circuit to receive first parity, second parity, and data read out from a first row of a memory device, and determine, based on a result of a first error detection operation using the first parity and a result of a second error detection operation using the second parity, whether the first row is faulty; a parity storage circuit to store a repair parity for repairing a fault of a row of a plurality of rows of the memory device, wherein the plurality of rows constitutes a repair unit, and wherein the repair unit includes the first row and one or more second rows; and a recovery circuit to repair a fault of the first row by using data of at least one of the second rows and the repair parity, when the first row is determined to be a faulty row.

Abstract: Data associated with a write request is stored at a storage device of multiple solid-state storage devices. A determination as to whether the data stored at the storage device is readable is made by determining whether a number of subsequent programming operations have been performed since the data was stored at the storage device. A notification that the stored data is readable from the storage device is generated upon determining that the data is readable.

Abstract: Methods, systems, and devices for operating a memory array with variable page sizes are described. The page size may be dynamically changed, and multiple rows of the memory array may be accessed in parallel to create the desired page size. A memory bank of the array may contain multiple memory sections, and each memory section may have its own set of sense components (e.g., sense amplifiers) to read or program the memory cells. Multiple memory sections may thus be accessed in parallel to create a memory page from multiple rows of memory cells. The addressing scheme may be modified based on the page size. The logic row address may identify the memory sections to be accessed in parallel. The memory sections may also be linked and accessing a row in one section may automatically access a row in a second memory section.

Abstract: This disclosure provides techniques hierarchical address virtualization within a memory controller and configurable block device allocation. By performing address translation only at select hierarchical levels, a memory controller can be designed to have predictable I/O latency, with brief or otherwise negligible logical-to-physical address translation time. In one embodiment, address transition may be implemented entirely with logical gates and look-up tables of a memory controller integrated circuit, without requiring processor cycles. The disclosed virtualization scheme also provides for flexibility in customizing the configuration of virtual storage devices, to present nearly any desired configuration to a host or client.

Abstract: A low-density parity check (LDPC) decoder includes a variable node unit (VNU) comprising a plurality of variable nodes configured to perform sums. A first message mapper of the LDPC decoder receives first n1-bit indices from likelihood ratio (LLR) input and maps the first n1-bit indices to first numerical values that are input to the variable nodes of the VNU. A second message mapper of the LDPC decoder receives second n2-bit indices from a check node unit (CNU) and maps the second n2-bit indices to second numerical values that are input to the variable nodes of the VNU. The CNU includes a plurality of check nodes that perform parity check operations. The first and second numerical values having ranges that are larger than what can be represented in n1-bit and n2-bit binary, respectively.

Abstract: The present disclosure generally relates to methods of operating storage devices. The storage device comprises a controller and a storage unit divided into a plurality of zones. Each zone comprises a plurality of dies, where each die comprises a plurality of erase blocks. Each erase block comprises a plurality of wordlines. One or more wordlines are grouped together in bins. Each bin is associated with a susceptibility weight, a read count weight, a timer count weight, and a running total weight. A weight counter table is stored in the controller, and tracks the various weights associated with each bin. When a sum of the weights of each bin reaches or exceeds a predetermined value, the controller closes the erase block to avoid an unacceptable quantity of bit error accumulation. The bit error susceptibility of an erase block decreases after the erase block is at capacity or is closed.

Abstract: Methods, systems, and devices for media scrubber operations in a memory system are described. A controller may, for example, count a quantity of forwarded code words in a memory medium during a scrubbing period. The controller may add the quantity to a total quantity of forwarded code words in the memory medium. The controller may refrain from forwarding additional code words based on the quantity. The controller may write a valid logic state to a spare bit when the spare bit is assigned to an erroneous bit in a code word. A separate memory cell may indicate a change in spare bit assignments and whether spare bits include valid logic states. The controller may retrieve a code word from a memory medium and invert one or more bits of the code word before writing the code word to the memory medium.

Abstract: Embodiments of the present disclosure provide a memory-efficient mechanism for identifying memory blocks with a low wear count. More particularly, embodiments of the present disclosure provide a mechanism for identifying a memory block whose wear count is within the bottom p % of all wear counts associated with memory blocks in a storage system. If a memory controller performs the garbage collection operation on a memory block whose wear count is within the bottom p % of all wear counts, then the memory controller is expected to utilize the remaining memory blocks (e.g., memory blocks whose wear count is within the upper (100-p) % of all wear counts) efficiently and level the wear count of at least the remaining memory blocks.

Abstract: An improved layered decoding method for a low density parity check (LDPC) code and a device therefor are disclosed. Disclosed is the layered decoding method for an LDPC code, capable of determining whether decoding is successful by performing a syndrome check on each check node at every variable node update. In addition, the syndrome check can be performed by using reduced variable nodes, thereby reducing decoding power consumption and decoding time consumption.

Abstract: Described herein are embodiments related to one-direction error recovery flow (ERF) operations on memory components of memory systems. A processing device determines that data from a read operation is not successfully decoded because of a partial write of the data. The partial write results from a number of memory cells written as a first state and read as a second state. The processing device performs a one-direction ERF on the memory cells by monotonically adjusting a read voltage level for one or more re-read operations from a first discrete read voltage level towards a second read voltage level in a first direction until the data from the one or more re-read operations is successfully decoded. The first direction corresponds to an opposite direction of a state shift of the partial write. The processing device can also can determine a directional EBC and perform a refresh write if necessary.

Abstract: In the field of data reading and writing technologies, a data writing method is associated with a data writing apparatus and an electronic device. The data writing method includes: determining whether a start storage address of a first data block is aligned with a bus bit width of a storage; in response to that the start storage address of the first data block is not aligned with the bus bit width of the storage, determining whether a second data block which is a data block immediately before the first data block is compressed; in response to that the second data block is compressed, executing complete writing on a first beat of the first data block.

Abstract: The invention introduces a method for handling sudden power off recovery, performed by a processing unit of an electronic apparatus, to include: driving a flash interface to program data sent by a host into pseudo single-level cell (pSLC) blocks of multiple logical unit numbers (LUNs) in a single-level cell (SLC) mode with multiple channels after detecting that the electronic apparatus has suffered a sudden power off (SPO). The pSLC blocks are reserved from being written any data in regular operations until the SPO is detected.

Abstract: A first group of memory cells of a memory device can be subjected to a particular quantity of program/erase cycles (PECs) in response to a programming operation performed on a second group of memory cells of the memory device. Subsequent to subjecting the first group of memory cells to the particular quantity of PECs, a data retention capability of the first group of memory cells can be assessed.

Abstract: Failure information associated with a plurality of blocks of a solid-state storage device of a plurality of solid-state storage devices is received. One or more blocks of the plurality of blocks storing uncorrectable data are identified based on the received failure information. A partial deallocation of the one or more blocks of the plurality of blocks is issued, the partial deallocation indicating that the one or more blocks store uncorrectable data. A remedial action associated with the one or more blocks of the plurality of blocks is performed.

Abstract: A storage device including control circuitry, communicatively coupled to a non-volatile memory, configured to receive a parity bit that has been stored using a data structure, and to receive a first subset of host data that includes block data relating to a set of memory cells. The control circuitry may be configured to perform a read operation to identify a second subset of host data that includes additional block data relating to the set of memory cells. The control circuitry may be configured to decode the second subset of host data using the parity bit. The control circuitry may be configured to perform a write operation to write the block data to at least one or more memory cells that are part of the set of memory cells.

Abstract: A method and apparatus for a CTC data copy operation, in that modification, and subsequent encoding only affects a small portion of metadata associated with copied data. By modifying and re-encoding only this small portion of metadata, a small portion of the parity data for the copied data requires updating. In embodiments where there are no errors in the read data to be copied (e.g., from an SLC portion of a NAND), decoding, modification, and encoding, may be done in parallel. Because such a small number of metadata bits are modified, in some embodiments, all possible codewords for the parity bits may be predetermined and combined (e.g., by XOR) to update the metadata parity bits.

Abstract: A memory system includes a non-volatile memory device and a controller. The non-volatile memory device includes a plurality of memory regions, each memory region including a plurality of cells commonly coupled to a word line. The controller generates a plurality of candidate data sets based on source data, determines a number of vulnerable cells corresponding to each of the plurality of candidate data sets, and stores a candidate data set having a smallest number of vulnerable cells into a target memory region among the plurality of memory regions.

Abstract: A non-volatile (NV) memory accessing method using data protection with aid of look-ahead processing, and associated apparatus such as memory device, controller and encoding circuit thereof are provided. The NV memory accessing method may include: receiving a write command and data from a host device; obtaining at least one portion of data to be a plurality of messages, to generate a plurality of parity codes through look-ahead type encoding, wherein regarding a message: starting encoding a first partial message to generate a first encoded result; applying predetermined input response information to a second partial message to generate a second encoded result, and combining the first and the second encoded results to generate a first partial parity code; and starting encoding the message to generate a second partial parity code, and outputting the first and the second partial parity codes to generate a parity code; and writing into the NV memory.

Abstract: A method performed by a controller of a solid state drive (SSD) comprising receiving from a host a write request to store write data in a nonvolatile semiconductor storage device of the SSD. The method also comprises identifying a first codeword and a second codeword stored in the nonvolatile storage device, the first codeword and the second codeword configured to store write data corresponding to the write request. Responsive to the write request, the method comprises writing a first portion of the write data to the first codeword and writing a second portion of the write data to the second codeword, and sending a message to the host once the write data has been written to the nonvolatile semiconductor storage device. The first and second codewords are adjacently stored, and the write data has a length that is greater than the length of the first and second codewords.

Abstract: The present disclosure generally relates to improved foggy-fine programming. The data to be written initially passes through an encoder before being written to SLC. While the data is being written to SLC, the data also passes through DRAM before going through the encoder to prepare for fine writing. The data that is to be stored in SLC is in latches in the memory device and is then written to MLC as a foggy write. Thereafter, the data that has passed through the encoder is fine written to MLC. The programming occurs in a staggered fashion where the ratio of SLC:foggy:fine writing is 4:1:1. To ensure sufficient XOR context management, programming across multiple dies, as well as across multiple super-devices, is staggered so that only four XOR parity context are necessary across 64 dies.

Abstract: A method of accessing a Solid State Disk (SSD) and an SSD are provided, where the SSD includes: a cache, N physical channels, and flashes mounted to the physical channels. The cache includes a plurality of strips. Each of the plurality of strips includes N sectors, N being an integer greater than or equal to 3. The method is applied to the SSD. According to the method, a data writing command for the SSD is received; a first strip and a first sector that correspond to an LBA of data to be written carried in the data writing command are determined; when the first strip is present in the cache, the data to be written is written into the cache as data of the first sector; and when the first strip is absent in the cache, the first strip is established and the data to be written is written into the cache as data of the first sector.

Abstract: The present disclosure is directed to logic based read sample offset operations in a memory sub-system. A processing device performs a first read, a second read, and a third read of data from a memory devices using a first center value corresponding to a first read level threshold, a negative offset value, and a positive offset value, respectively. The processing device performs a XOR operation on results from the first and second reads to obtain a first value and a XOR operation on results from the second and third reads to obtain a second value. The processing device performs a first count operation on the first value to determine a first difference bit count and a second count operation on the second value to determine a second difference bit count. The processing device can store or output the first difference bit count and the second difference bit count.

Abstract: A processing device determines a set of difference error counts corresponding to multiple programming distributions of a memory sub-system. A valley having a lowest valley margin is identified based on a comparison of the set of difference error counts. Based on the set of difference error counts, a program targeting rule from a set of rules. A program targeting operation is performed, based on the program targeting rule, a program targeting operation to adjust a voltage associated with an erase distribution of the memory sub-system.

Abstract: A storage device includes one or more FMPKs including a FM chip capable of storing data and a storage controller that controls storing of write data of a predetermined write request for the FMPK. The FMPK includes a compression/decompression circuit that compresses data according to a second compression algorithm different from a first compression algorithm. The storage controller compresses data using the first compression algorithm, and determines whether the write data will be compressed using the storage controller or the compression/decompression circuit based on a predetermined condition. The write data is compressed by the determined storage controller or compression/decompression circuit and is stored in the FMPK.

Abstract: A method for error correction in a memory system includes determining a bit error ratio for a memory block of the memory system during a read operation. The method further includes determining whether the bit error ratio is between a first threshold and a second threshold. The method further includes based on a determination that the bit error ratio is between the first threshold and the second threshold, performing a select gate drain (SGD) read operation on a SGD word line of the memory block. The method further includes generating first soft bit data using SGD data corresponding to the SGD read operation. The method further includes performing a low-density parity-check correction using the first soft bit data on the memory block.

Abstract: A computer-implemented method, according to one embodiment, includes: performing a first read of one or more pages in a first page region of a first block. In response to determining that the highest RBER experienced during the first read is not in a first predetermined range, a first calibration procedure is performed on the one or more pages. A second read of the one or more pages is performed. In response to determining that the highest RBER experienced during the second read is not in a second predetermined range, a second calibration procedure on the one or more pages is performed, and a third read of the one or more pages is performed. In response to determining that the highest RBER experienced during the third read is not in the second predetermined range, a reliability counter which corresponds to the first page region of the first block is incremented.

Abstract: Disclosed in some examples are methods, systems, storage devices, and machine readable mediums that utilize the ability of ECC to correct errors to actively prevent errors. The memory device determines whether a request to place data of a requested value at a requested location in the storage media is likely to interfere with other data stored at other locations on the storage media, and if so, changes the requested value to a second value that will not interfere (or has a lower probability of interfering) with neighboring data. The second value may be corrected to the requested value when a read request is made for that data using ECC.

Abstract: An example apparatus to monitor memory includes an error manager to compare a first memory location of a first error in the memory to a plurality of memory locations in an error history log, the plurality of memory locations previously identified in the error history log based on errors detected in the memory locations, ones of the memory locations associated with corresponding counters that track the errors detected in the memory locations, and update a first one of the counters corresponding to the first memory location when a first address of the first memory location matches a second address of one of the memory locations in the error history log. The example apparatus further includes a command generator to transmit a command to an error corrector to perform error correction on the first memory location when the first one of the counters satisfies a threshold.

Abstract: Systems, apparatuses, and methods related to three tiered hierarchical memory systems are described herein. A three tiered hierarchical memory system can leverage persistent memory to store data that is generally stored in a non-persistent memory, thereby increasing an amount of storage space allocated to a computing system at a lower cost than approaches that rely solely on non-persistent memory. An example apparatus may include a persistent memory, and one or more non-persistent memories configured to map an address associated with an input/output (I/O) device to an address in logic circuitry prior to the apparatus receiving a request from the I/O device to access data stored in the persistent memory, and map the address associated with the I/O device to an address in a non-persistent memory subsequent to the apparatus receiving the request and accessing the data.

Abstract: A black box device for a vehicle includes a data storage system for recording event data fed to the black box from various vehicle sensors. The data storage system includes a memory having memory cells and a controller in communication with the memory. The controller is configured to receive data and determine one or more memory cells as a destination for the data to be written. The controller is configured to determine a wear level of the memory cells and select a subset of program states of the memory cells based on the wear level; and program the memory cells using respective subsets of program states for each respective memory cell.

Abstract: A memory system includes a memory device configured to store data through a write operation and output the stored data as read data through a read operation; a buffer memory configured to store the read data output from the memory device; a controller configured to control the memory device such that the memory device performs the read operation in response to a read request received from a host, and to control the buffer memory to store the read data in the buffer memory. When the read request corresponds to an asynchronous read operation, the controller may allocate a partial area of the buffer memory as storage space for the read data after the read operation of the memory device is completed.

Abstract: A nonvolatile memory device includes a memory cell array, a page buffer including a first latch configured to store data to be programmed in a first state, a second latch configured to store the data in a second state, and a third latch configured to store the data in a third state when the data is received from an external apparatus, and a control logic configured to control the page buffer to store the data of the first state in the first latch, the data of the second state in the second latch, and the data of the third state in the third latch when a multi-conversion program command and the data are received from the external apparatus.

Abstract: A system includes a plurality of solid-state storage devices and a storage controller coupled to the plurality of solid-state storage devices. The storage controller includes a processing device, the processing device to receive a write request from a host computing device. The write request includes data to be stored at one or more of the plurality of solid-state storage devices. The processing device is to send an acknowledgement to the host computing device in response to receipt of the write request, store the data at the one or more of the plurality of solid-state storage devices, determine whether the data stored at the one or more of the plurality of solid-state storage devices is readable, and in response to determining that the data is readable, notify, by the processing device, the host computing device that the stored data is readable from the one or more of the plurality of solid-state storage devices.

Abstract: A computer-implemented method includes encoding an array of (p?1)×k symbols of data into a p×(k+r) array. The method includes p is a prime number, r?1, and k?p. The method includes each column in the p×(k+r) array has an even parity and symbol i in column r+j, for 0?i?p?1 and 0?j?r?1, is the XOR of symbols in a line of slope j taken with a toroidal topology modulo p in the k columns starting in symbol i of column 0.

Abstract: The present invention discloses a system for storing a blockchain on a distributed network. The system includes a distributed network containing a plurality of nodes. The system stripes a blockchain into individual blocks where each individual block is separately encrypted and stored on a different node of the distributed network. The system forms a parity block from the individual blocks striped from the single blockchain. The parity block is separately encrypted and stored on a node of the distributed network separate from the other nodes storing the individual blocks for the blockchain. The system uses a blockchain distributed network map identifying where all of the individual blocks and the parity block are stored on the distributed network to reassemble all of the individual blocks into an undivided single blockchain.

Abstract: Embodiments described herein provide a system for facilitating modulation-assisted error correction. The system can include a plurality of flash memory cells, an organization module, a mapping module, and a modulation module. During operation, the organization module groups bits of a cluster of cells in the plurality of flash memory cells into a first group and a second group. A respective of the first and second groups includes bits from a respective cell of the cluster of cells. The mapping module generates a modulation map that maps a subset of bits indicated by the first group in such a way that the subset of bits is repeated in a respective domain of bits indicated by the second group. The modulation module then programs user data bits in the cluster of cells based on the modulation map.

Abstract: A memory system includes: a memory cell array including a plurality of memory blocks; a peripheral circuit configured to perform a read operation on a selected memory block among the plurality of memory blocks and a backup program operation on a backup block among the plurality of memory blocks; and a control circuit configured to control the peripheral circuit to backup data of logical pages included in the selected memory block in the backup block, when a read count of a selected physical page of the selected memory block is equal to or larger than a set value in the read operation on the selected memory block.

Abstract: A data storage device is provided. The data storage device includes a flash memory and a controller. The flash memory includes a plurality of blocks for storing data and each block includes a plurality of pages. The controller is configured to convert a host read command into a read-operation instruction to the flash memory to perform a default read operation to read page data from the flash memory. The default read operation has a default read threshold voltage. In response to a failure of the default read operation, the controller is configured to sequentially perform a read operation on the flash memory using a read threshold voltage with respect to each entry of a plurality of entries in a read-retry table, and replace the default read threshold voltage with the read threshold voltage corresponding to the read operation being successfully performed.

Abstract: Examples include techniques for emulating a non-volatile dual inline memory module (NVDIMM) in a computing platform using a non-volatile storage device. When a power up event occurs for the computing platform, a host memory buffer may be allocated in a system memory device and a backing store for the host memory buffer may be copied from the non-volatile storage device to the host memory buffer in the system memory device. When a power down event or a flush event occurs for the computing platform, the host memory buffer may be copied from the system memory device to the corresponding backing store for the host memory buffer in the non-volatile storage device. Thus, virtual NVDIMM functionality may be provided without having NVDIMM hardware in the computing platform.

Abstract: A memory system includes: a memory device including a plurality of memory blocks; and a controller suitable for selecting one or more first memory blocks based on a predetermined condition among the plurality of the memory blocks in a booting section, and increasing a read reclaim count value of one or more second memory blocks among the one or more first memory blocks for which a number of failed bits of read data exceeds a predetermined threshold.

Abstract: The present disclosure includes apparatuses and methods for proactive corrective actions in memory based on a probabilistic data structure. A number of embodiments include a memory, and circuitry configured to input information associated with a subset of data stored in the memory into a probabilistic data structure and proactively determine, at least partially using the probabilistic data structure, whether to take a corrective action on the subset of data stored in the memory.

Abstract: A memory device can include three-dimensional memory entities each including a plurality of two-dimensional memory entities. A controller can read data from the memory at a first resolution and collect error rate information from the memory at a second resolution including a portion of a two-dimensional memory entity. The controller can determine a quantity of two-dimensional memory entities that have a greater error rate than a remainder of the two-dimensional memory entities based on the error rate information. The controller can determine a quantity of portions of three-dimensional memory entities that have a greater error rate than a remainder of the portions of three-dimensional memory entities based on the error rate information excluding error rate information for portions of the two-dimensional memory entities associated with the quantity of two-dimensional memory entities.

Abstract: A first error-detecting code (EDC) is computed based on a first segment of a block of information that is to be encoded, and a second EDC is computed based on at least a second segment of the block of information. The first EDC is masked with a first masking segment and the second EDC with a second masking segment to generate a first masked EDC and a second masked EDC. The first masking segment and the second masking segment are associated with a target receiver of the block of information. A codeword is generated based on a code and an input vector that includes the first segment, the first masked EDC, the second segment, and the second masked EDC. This type of coding could be useful to support early termination of blind detection at a decoder, for example.

Abstract: The present disclosure includes apparatuses and methods for in-memory operations. An example apparatus includes a memory device including a plurality of subarrays of memory cells, where the plurality of subarrays includes a first subset of the respective plurality of subarrays and a second subset of the respective plurality of subarrays. The memory device includes sensing circuitry coupled to the first subset, the sensing circuitry including a sense amplifier and a compute component. The apparatus also includes a controller configured to direct a first movement of a number of data values from a subarray in the second subset to a subarray in the first subset and performance of a sequential plurality of operations in-memory on the number of data values by the first sensing circuitry coupled to the first subset.

Abstract: A storage system includes: a control processor, configured to: read user data with a read threshold, detect an uncorrectable error in the user data, detect a sector balanced when the number of 1's and 0's in the user data is within the difference stored in a range register, apply an XOR RAID recovery to correct the uncorrectable error in the user data; and a non-volatile memory array, coupled to the control processor, configured to store the user data; and wherein the control processor is further configured to forego an additional read of a sector N with a different value of the read threshold when the sector balanced initiates the XOR RAID recovery.

Abstract: Improving performance of a read in a memory system. Various methods include: reading data from a word line in a memory block, where during the read, associated parameters are generated that include: a value indicative of a throughput time, and a value indicative of a bit error rate (BER); retrieving the value indicative of the throughput time and the value indicative of the BER; and performing a read improvement process if the value indicative of the throughput time is above a threshold value. The method also includes performing the read improvement process by: flagging the memory block if the value indicative of the BER is at or below and expected BER; and performing cleanup operations if the value indicative of the BER is higher than the expected BER.

Abstract: A storage system includes memory cells arranged in an array and a memory controller coupled to the memory cells for controlling operations of the memory cells. The memory controller is configured to perform a read operation in response to a read command from a host, perform a first soft decoding of data from the read operation using existing LLR (log likelihood ratio) values stored in the memory controller, update existing LLR values using LLR values from neighboring memory cells and existing weight coefficients that account for influence from the neighboring memory cells. The memory controller is also configured to perform a second soft decoding using the updated LLR values. If the second soft decoding is successful, the memory controller performs a recursive update of weight coefficients to reflect updated influence from neighboring memory cells and stores the updated weight coefficient in the memory controller for use in further decoding.

Abstract: A non-volatile (NV) memory accessing method using data protection with aid of look-ahead processing, and associated apparatus such as memory device, controller and encoding circuit thereof are provided. The NV memory accessing method may include: receiving a write command and data from a host device; obtaining at least one portion of data to be a plurality of messages, to generate a plurality of parity codes through look-ahead type encoding, wherein regarding a message: starting encoding a first partial message to generate a first encoded result; applying predetermined input response information to a second partial message to generate a second encoded result, and combining the first and the second encoded results to generate a first partial parity code; and starting encoding the message to generate a second partial parity code, and outputting the first and the second partial parity codes to generate a parity code; and writing into the NV memory.