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 non-volatile memory, a resource managing unit that reclaims resources associated with the non-volatile memory and increases the resources, when the usage of the resources associated with the non-volatile memory reaches the predetermined amount, a transmission rate setting unit that calculates a setting value of the transmission rate to receive the write data from a host device, and a transmission control unit that receives the write data from the host device and transmits the received write data to the non-volatile memory. The transmission rate setting unit calculates a small setting value when the usage of the resources associated with the non-volatile memory increases. The transmission control unit executes the reception of the write data from the host device at the transmission rate of the setting value, while the resource managing unit reclaims the resources.

Abstract: According to one embodiment, a controller controls writing into and reading from a storage apparatus that includes a first data-storage unit and a second data-storage unit. The second data-storage unit stores user data and parity data of the user data. The first data-storage unit stores the parity data. The controller includes a parity updating unit and a parity writing unit. When parity data is updated, the parity updating unit writes the updated parity data into the first data-storage unit. When a certain requirement is satisfied, the parity writing unit reads the parity data written in the first data-storage unit, and writes the parity data thus read into the second data-storage unit.

Abstract: A semiconductor storage device includes a first memory area configured in a volatile semiconductor memory, second and third memory areas configured in a nonvolatile semiconductor memory, and a controller which executes following processing. The controller executes a first processing for storing a plurality of data by the first unit in the first memory area, a second processing for storing data outputted from the first memory area by a first management unit in the second memory area, and a third processing for storing data outputted from the first memory area by a second management unit in the third memory area.

Abstract: As a semiconductor storage device that can efficiently perform a refresh operation, provided is a semiconductor storage device comprising a non-volatile semiconductor memory storing data in blocks, the block being a unit of data erasing, and a controlling unit monitoring an error count of data stored in a monitored block selected from the blocks and refreshing data in the monitored block in which the error count is equal to or larger than a threshold value.

Abstract: A semiconductor storage device includes a first memory area configured in a volatile semiconductor memory, second and third memory areas configured in a nonvolatile semiconductor memory, and a controller which executes following processing. The controller executes a first processing for storing a plurality of data by the first unit in the first memory area, a second processing for storing data outputted from the first memory area by a first management unit in the second memory area, and a third processing for storing data outputted from the first memory area by a second management unit in the third memory area.

Abstract: A semiconductor storage device includes a first memory area configured in a volatile semiconductor memory, second, third, and fourth memory areas configured in a nonvolatile semiconductor memory, and a controller which executes following processing. The controller executes a first processing for storing a plurality of data by the first unit in the first memory area, a second processing for storing data by a first management unit in the fourth memory area, a third processing for storing data by a second management unit in the third memory area, a fourth processing for moving an area of the third unit having the oldest allocation order in the fourth memory area to the second memory area, and a fifth processing for selecting data in the second memory area and copying the selected data to an empty area of the third unit in the second memory area.

Abstract: A semiconductor storage device can efficiently perform a refresh operation. A semiconductor storage device is provided which includes a non-volatile semiconductor memory storing data in blocks, the block being a unit of data erasing. A controlling unit is further included monitoring an error count of data stored in a monitored block selected from the blocks and for refreshing data in the monitored block in which the error count is equal to or larger than a threshold value.

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: 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 memory system includes a nonvolatile memory including blocks as data erase units, a measuring unit which measures an erase time at which data in each block is erased, a block controller having a block table which associates a state value indicating one of a free state and a used state with the erase time for each block, a detector which detects blocks in which rewrite has collectively occurred within a short period, a first selector which selects a free block having an old erase time as a first block, a second selector which selects a block in use having an old erase time as a second block, and a leveling unit which moves data in the second block to the first block if the first block is included in the blocks detected by the detector.

Abstract: A memory system includes a nonvolatile memory including a plurality of blocks as data erase units, a measuring unit which measures an erase time at which data of each block is erased, and a block controller which writes data supplied from at least an exterior into a first block which is set in a free state and whose erase time is oldest.

Abstract: A memory system includes a volatile first storing unit, a nonvolatile second storing unit, and a controller. The controller performs data transfer, stores management information including a storage position of the data stored in the second storing unit into the first storing unit, and performs data management while updating the management information. The second storing unit has a management information storage area for storing management information storage information including management information in a latest state and a storage position of the management information. The storage position information is read by the controller during a startup operation of the memory system and includes a second pointer indicating a storage position of management information in a latest state in the management information storage area and a first pointer indicating a storage position of the second pointer.

Abstract: A semiconductor storage device includes first, second, third, fourth and fifth memory areas and a controller which executes following processing. The controller executes a first processing for storing a plurality of data by the first unit in the first memory area, a second processing for storing data by a first management unit in the fourth memory area, a third processing for storing data by a second management unit in the fifth memory area, a fourth processing for moving an area of the third unit to the second memory area, a fifth processing for selecting and copying data to an empty area of the third unit in the second memory area, a sixth processing for moving an area of the third unit to the third memory area, and a seventh processing for selecting and copying data to an empty area of the third unit in the third memory area.

Abstract: A memory system includes a nonvolatile memory including blocks as data erase units, a measuring unit which measures an erase time at which data in each block is erased, a block controller having a block table which associates a state value indicating one of a free state and a used state with the erase time for each block, a detector which detects blocks in which rewrite has collectively occurred within a short period, a first selector which selects a free block having an old erase time as a first block, a second selector which selects a block in use having an old erase time as a second block, and a leveling unit which moves data in the second block to the first block if the first block is included in the blocks detected by the detector.

Abstract: A semiconductor storage device includes a first memory area configured in a volatile semiconductor memory, second, third and fourth memory areas configured in a nonvolatile semiconductor memory, and a controller which executes following processing. The controller executes a first processing for storing a plurality of data by the first unit in the first memory area, a second processing for storing data by a first management unit in the fourth memory area, a third processing for storing data by a second management unit in the third memory area, a fourth processing for moving an area of the third unit from the fourth memory area to the second memory area, a fifth processing for copying data to an area of the third unit and allocating the area to the second memory area, and a sixth processing for copying data to an empty area of the third unit in the second memory area.

Abstract: A memory system includes a nonvolatile memory including blocks as data erase units, a measuring unit which measures an erase time at which data in each block is erased, a block controller having a block table which associates a state value indicating one of a free state and a used state with the erase time for each block, a detector which detects blocks in which rewrite has collectively occurred within a short period, a first selector which selects a free block having an old erase time as a first block, a second selector which selects a block in use having an old erase time as a second block, and a leveling unit which moves data in the second block to the first block if the first block is included in the blocks detected by the detector.

Abstract: A memory system according to an embodiment of the present invention comprises: a memory amount required for management table creation is reduced by adopting a nonvolatile semiconductor memory including a plurality of parallel operation elements respectively having a plurality of physical blocks as units of data erasing and a controller that can drive the parallel operation elements in parallel and has a number-of-times-of-erasing managing unit that manages the number of times of erasing in logical block units associated with a plurality of physical blocks driven in parallel.

Abstract: As a semiconductor storage device that can efficiently perform a refresh operation, provided is a semiconductor storage device comprising a non-volatile semiconductor memory storing data in blocks, the block being a unit of data erasing, and a controlling unit monitoring an error count of data stored in a monitored block selected from the blocks and refreshing data in the monitored block in which the error count is equal to or larger than a threshold value.

Abstract: A memory system includes a nonvolatile memory including a plurality of blocks as data erase units, a measuring unit which measures an erase time at which data of each block is erased, and a block controller which writes data supplied from at least an exterior into a first block which is set in a free state and whose erase time is oldest.