摘要:
In rewriting processing of logical sectors, data of the transferred logical sectors are temporarily stored in a memory buffer. When the buffer memory has been full filled with data, the data is written into a flash memory. In rewriting processing for the flash memory including a writing unit (page) having a capacity larger than a minimum writing unit (sector) from outside, the number of executions of the evacuation processing can be reduced and the fast data rewriting can be performed. Thus, it is possible to rationalize the evacuation processing for old data caused in the rewriting in units of sectors and to improve the data rewriting speed.
摘要:
A nonvolatile storage device is provided with a nonvolatile main storage memory (114) whose erase size is larger than a cluster size, and a buffer (106), i.e. a nonvolatile auxiliary storage memory. At the time of writing data in the memory, the data is temporarily stored in the buffer (106), then, a plurality of data in the buffer (106) are collectively taken out to be stored in the main storage memory (114). Data in an original block is saved in a write block in the main storage memory. Thus, the data can be written in the main storage memory (114) at a high speed.
摘要:
The invention presents a memory controller capable of shortening the creation time of address management table at the time of initialization of memory card, while avoiding decline of access speed due to process of writing back the address management table in normal operation.The memory controller 114 includes a read-write memory 113 for temporarily storing the address management table 112, a memory control unit 122 for writing, in a nonvolatile memory 115, an address management table temporarily stored in the read-write memory and address range specifying information for specifying the changeover destination address range, when the physical block of data writing destination is changed over from a certain address range to other address range, and an address management table generation unit 107 for reading out the distributed management information used for managing the state of physical block included in the address range specified based on the address range specifying information at the time of initialization, and generating the address management table 112 based on the distributed management information being read out.
摘要:
A writing completion flag table (105) for storing a writing completion flag corresponding to a predetermined storage unit such as a cluster or a physical block is stored in a non-volatile control memory (106). When completion of data writing into a predetermined storage unit is detected, a write completion flag is written in the corresponding address of the storage unit on the write completion flag table (105). Thus, it is possible to recognize that data has been written normally. Even when the flag indicating completion of writing into a page of the writing unit of the main storage memory cannot be written, it is possible to improve the writing reliability.
摘要:
With nonvolatile memory device employing a nonvolatile memory suc h as multiple-valued NAND flash memory or the like in which each memory cell holds data in a plurality of pages, there is such a problem that, if an error occurred under writing data, data stored in other page in the same group of the current page is changed, and hence the object of the present invention is to solve this problem. In writing data into a nonvolatile memory 110, when error occurred under writing data into a certain page, an error page identification part 128 identifies an error type and a physical address of the page where error occurred. An error corrector 129 then corrects errors occurred in other pages belonging to the same group of error occurrence page.
摘要:
A semiconductor memory device in which data is not written in a transfer destination under a state including an error when an error occurs at the time of reading data at the transfer destination. The semiconductor memory device (1) comprising a nonvolatile memory (2) having a data writing unit smaller than a physical block is provided with an error detecting/correcting circuit (23) in the non-volatile memory (2). When data stored in a specified block of the non-volatile memory (2) is transferred to a different physical block and written, the error detecting/correcting circuit (23) performs error detection and correction of data.
摘要:
A controller 102 and four flash memories F0 to F3 are connected by twos to two memory buses, and each flash memory is divided into two regions of substantially the same size to form a first half and a last half regions. In a four-memory configuration, a consecutive logical address specified by a host apparatus is divided into a predetermined size, and a write operation is performed in a format that repeatedly circulates through F0, F1, F2, F3 in this order. In a two-memory configuration, the write operation is performed in a format that repeatedly circulates through F00, F10, F01, F11. Thus, a controller processing is made common regardless of the number of flash memories connected to the controller.
摘要:
A writing completion flag table that stores a writing completion flag corresponding to a predetermined storage, such as a cluster or a physical block, is stored in a non-volatile control memory. When completion of data writing into a predetermined storage is detected, a write completion flag is written in the corresponding address of the storage on the write completion flag table. Thus, it is possible to recognize that data has been written normally. Even when the flag indicating completion of writing into a page of the writing unit of the main storage memory cannot be written, it is possible to improve the writing reliability.
摘要:
A physical area management table (105) and a pointer table (106) are stored in a nonvolatile auxiliary storage memory (107). When a logical-physical conversion table (108) is updated (restored) in a main storage memory (140), the restored area is determined in a re-arrangement way by the pointer table to avoid rewrite concentration on the main storage memory (140). Immediately after data is written in the main storage memory (140), the state of the physical block on the physical area management table (105) is updated. Consequently, even if power interruption occurs, it is possible to reliably judge if the data is valid or not.
摘要:
A semiconductor memory device in which data is not written in a transfer destination under a state including an error when an error occurs at the time of reading data at the transfer destination. The semiconductor memory device (1) comprising a nonvolatile memory (2) having a data writing unit smaller than a physical block is provided with an error detecting/correcting circuit (23) in the non-volatile memory (2). When data stored in a specified block of the non-volatile memory (2) is transferred to a different physical block and written, the error detecting/correcting circuit (23) performs error detection and correction of data.