Patent ID: 7240178

Claim:
A nonvolatile memory comprising a physical block as a storage unit, said physical block having a data area for storing data and a redundant area for storing various management information, wherein each said redundant area includes: a logical block information storing area for storing information for identifying a logical block corresponding to a physical block including said redundant area; a previously used physical block information storing area for storing information for identifying a previously used physical block, which is an immediately preceding physical block with which the corresponding logical block was associated; and a status information storing area for storing status information for distinguishing a state of operation in each stage occurring in performing data rewriting operation using the physical block including said redundant area for data writing; and wherein said status information storing area stores at least first status information indicating that the physical block including said status information storing area is in an erased state, second status information indicating that while data writing to the physical block including said status information storing area is completed, data of the corresponding previously used physical block is not erased, and third status information indicating that data writing to the physical block including said status information storing area is completed and that the data of the corresponding previously used physical block is erased.