Patent ID: 7070113

Claim:
A memory card comprising: nonvolatile memory; and a control circuit, wherein a memory array of said nonvolatile memory has an erase table in which a free-space information flag is associated with each physical address of a memory area, wherein said free-space information flag has one of a first status and a second status, wherein said first status is indicating that the corresponding memory area is permitted to be erased and a second status indicating that the corresponding memory area is inhibited to be erased, wherein said control circuit refers to said erase table for search of a memory area to which rewrite data is written, and wherein said control circuit is adapted to store into a predetermined area of said nonvolatile memory an updated version of the erase table, which includes an updated free-space information flag from a previous version of the erase table, the predetermined area being a different area than an area in which the previous version of the erase table is stored.