Abstract:
According to one embodiment, a command generator sequentially and speculatively issues channel-by-channel access commands to a memory interface in a predetermined access process. A purger returns a series of unexecuted already-issued access commands using a purge response if an error occurs in any of memory accesses via a plurality of channels. A command progress manager updates command progress information such that the command progress on each of the plurality of channels returns to a position specified in an oldest access command of a series of the returned access commands issued to the channel. The command generator issues the channel-by-channel access commands including the oldest access command to the memory interface based on the updated command progress information.
Abstract:
PROBLEM TO BE SOLVED: To provide a memory apparatus capable of reducing a time required for processing a replacement when a write-in error occurs by a deterioration of write-in property of a memory cell, and to provide a memory controlling method and a program.SOLUTION: The memory 140 has: a function of issuing a fact of defective cell to a memory controller 130 by an occurrence of error when the time required for the write-in is not completed within a predetermined period; a function of replacement process for changing over the memory cell of a main memory area where the error occurs, with the memory cell of a replacement area; and a save area having a plurality of areas for saving by making an address and data of the defective memory cell as a pair, and each save area includes a flag which shows the using state or unused state. The memory holds a new defective address and data in the unused area of save area when the defective cell newly occurs, and it includes a function to set the flag to be the using state and a function to make the flag to be the unused state when the replacement process is executed and information of the save area becomes unnecessary.
Abstract:
PROBLEM TO BE SOLVED: To surely receive data from a DQ signal according to the rising and falling of a DQS signal. SOLUTION: A memory control device 2 includes: a receiver circuit 20 which delays a DQS signal whose rising edge and falling edge appear in a fixed cycle, and generates a plurality of delay DQS signals having delay times different from each other; a data extraction part 210 for extracting the data of a section corresponding to the rising edge or falling edge of the generated delay DQS signal from a DQ signal partially having already known reference data; a data determination part 240 for determining whether or not the extracted data are matched with reference data; and an upper and lower limit value determination part 250 for determining the range of the delay time corresponding to the rising edge of the DQS signal and the range of the delay time corresponding to the falling edge of the DQS signal from the delay time of the delay DQS signal corresponding to the data determined to coincide. COPYRIGHT: (C)2010,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide a memory system having a NAND flash memory using a multi-valued memory that can protect written data against destruction upon a hit or the like during writing to a higher page. SOLUTION: The memory system includes a first, volatile storage part, a second, nonvolatile storage part comprising an array of a plurality of memory cells capable of storing multi-valued data which have a plurality of pages, and a controller for implementing data transfer between the second storage part and a host device via the first storage part. The controller has a migration part 155 for, if data has been written in the lower page that is on the same memory cell as the page to which data are to be written on a write-once basis, backing up the data in the lower page before the data are written to the second storage part, and a destructive information recovery part 156 for, if the data in the lower page are destructed, recovering the destructed data by the use of the backup data. COPYRIGHT: (C)2009,JPO&INPIT