Abstract:
According to one embodiment, a semiconductor storage device includes a nonvolatile semiconductor memory, a temporary storage buffer that temporarily stores writing data to be written to the nonvolatile semiconductor memory, and a coding processing unit that divides coding target data of an error correction code into two or more divided data and writes an error correction code obtained by performing an error correction coding process based on the divided data stored in the temporary storage buffer to the temporary storage buffer as an intermediate code.
Abstract:
According to one embodiment, a semiconductor storage device includes a nonvolatile semiconductor memory, a temporary storage buffer that temporarily stores writing data to be written to the nonvolatile semiconductor memory, and a coding processing unit that divides coding target data of an error correction code into two or more divided data and writes an error correction code obtained by performing an error correction coding process based on the divided data stored in the temporary storage buffer to the temporary storage buffer as an intermediate code.
Abstract:
According to an embodiment, a semiconductor storage device includes an error correction processing unit that executes encoding process related data to be dispersedly written over a plurality of memory areas and decoding process related data dispersedly written over the plurality of memory areas. A transfer management unit determines whether or not data related to the data transfer request is a target of the error correction process and causes the error correction processing unit to execute the error correction process only with respect to the data determined as the target of the error correction process.
Abstract:
According to one embodiment, write data is written in a nonvolatile semiconductor memory with a first error correction code and a second error correction code attached to the write data. The first error correction code and the write data are read out from the nonvolatile semiconductor memory to perform first error correction processing. When there is a remaining error, the second error correction code corresponding to the write data is read out to carry out second error correction processing.
Abstract:
According to one embodiment, a memory system includes a chip including a cell array and first and second caches configured to hold data read out from the cell array; an interface configured to manage a first and a second addresses; a controller configured to issue a readout request to the interface; and a buffer configured to hold the data from the chip. The interface transfers the data in the first cache to the buffer without reading out the data from the cell array if the readout address matches the first address, transfers the data in the second cache to the buffer without reading out the data from the cell array if the readout address matches the second address, and reads out the data from the cell array and transfers the data to the buffer if the readout address does not match either one of the first or second address.
Abstract:
According to one embodiment, a memory system includes a chip including a cell array and first and second caches configured to hold data read out from the cell array; an interface configured to manage a first and a second addresses; a controller configured to issue a readout request to the interface; and a buffer configured to hold the data from the chip. The interface transfers the data in the first cache to the buffer without reading out the data from the cell array if the readout address matches the first address, transfers the data in the second cache to the buffer without reading out the data from the cell array if the readout address matches the second address, and reads out the data from the cell array and transfers the data to the buffer if the readout address does not match either one of the first or second address.
Abstract:
According to one embodiment, a memory system includes a chip including a cell array and first and second caches configured to hold data read out from the cell array; an interface configured to manage a first and a second addresses; a controller configured to issue a readout request to the interface; and a buffer configured to hold the data from the chip. The interface transfers the data in the first cache to the buffer without reading out the data from the cell array if the readout address matches the first address, transfers the data in the second cache to the buffer without reading out the data from the cell array if the readout address matches the second address, and reads out the data from the cell array and transfers the data to the buffer if the readout address does not match either one of the first or second address.
Abstract:
According to an embodiment, an encoding apparatus includes a parameter holding unit configured to hold a parameter; an error-detecting code holding unit configured to hold an error-detecting code that is generated from the parameter; an error detecting unit configured to detect an error in the parameter, which is held in the parameter holding unit, with the use of the error-detecting code held in the error-detecting code holding unit; an error correcting unit configured to correct the error detected by the error detecting unit; a selecting unit configured to select the parameter that has been subjected to error correction by the error correcting unit; and an encoding unit configured to encode data with the use of the parameter selected by the selecting unit.
Abstract:
A WC resource usage is compared with an auto flush (AU) threshold Caf that is smaller than an upper limit Clmt, and when the WC resource usage exceeds the AF threshold Caf, the organizing state of a NAND memory 10 is checked. When the organizing of the NAND memory 10 has proceeded sufficiently, data is flushed from a write cache (WC) 21 to the NAND memory 10 early, so that the response to the subsequent write command is improved.
Abstract:
A method of controlling a nonvolatile semiconductor memory including a plurality of blocks, each one of the plurality of blocks being a unit of data erasing, includes determining a monitored block as a candidate for refresh operation from among the plurality of blocks based on a predetermined condition. The method includes monitoring an error count of data stored in the monitored block and not monitoring an error count of data stored in blocks excluding the monitored block among the plurality of blocks. The method also includes performing the refresh operation on data stored in the monitored block in which the error count is larger than a first threshold value.