Patent ID: 8819332

Claim:
A nonvolatile storage device, comprising: a nonvolatile memory configured from a plurality of blocks which serve as erasing units, including a plurality of pages which serve as writing units; and a memory controller which performs writing and reading of data to and from the nonvolatile memory, wherein the nonvolatile memory includes a copy mode storage area capable of storing copy modes for deciding a method of copying data to the respective blocks, in association with the respective blocks, wherein the memory controller includes: an access control unit which controls a writing operation and a reading operation of data to and from the nonvolatile memory; and an error correction control unit which performs error correction of data stored in the nonvolatile memory, wherein the copy modes include N types (N is a natural number of 2 or higher) of copy modes from a first copy mode to an Nth copy mode, wherein each of the first to Nth copy modes defines, for each page, either a first copy method which copies data after performing the error correction by the error correction control unit, or a second copy method which copies data without performing the error correction by the error correction control unit, wherein each of the pages is associated with the first copy method in one or more copy modes among the first to Nth copy modes, and associated with the second copy method in other copy modes, wherein each of the first to Nth copy modes includes a page which is associated with the first copy method and a page which is associated with the second copy method, wherein a page subsequent to a page associated with the first copy method is associated with the second copy method in each of the first to Nth copy modes, and a page associated with the first copy method in the first copy mode is associated with the second copy method in a second copy mode subsequent to the first copy mode, and wherein upon copying data stored on a page in a copy source block to a page in a copy destination block, (i) the access control unit, according to a copy mode associated with the copy source block stored in the copy mode storage area (a) copies data stored on the page in the copy source block to the page in the copy destination block after performing the error correction by the error correction control unit when the page in the copy source block is associated with the first copy method, and (b) copies data stored on the page in the copy source block to the page in the copy destination block without performing the error correction by the error correction control unit when the page in the copy source block is associated with the second copy method, and (ii) the access control unit changes a copy mode associated with the copy destination block to a copy mode that is different from the copy mode associated with the copy source block.