Patent ID: 8370564

Claim:
An access control device that writes data to each of predetermined storage block sets in a storage device of which a storage area has been divided into a plurality of storage blocks, the control device comprising: a memory to store, for each of said storage blocks, record enable/disable information indicating whether said storage block is a non-defective block in which the data can be recorded or a defective block in which the data cannot be recorded; and a processor, when the data is written to each of said storage block sets, to write the data only to non-defective blocks in said storage block set, based on the record enable/disable information stored in the memory, wherein among a plurality of said storage block sets, the processor determines at least one of the storage block sets, in which all the storage blocks belonging thereto are non-defective blocks, as a first storage block set for writing dummy data, and when the data is written to a second storage block set including a defective block, the processor writes the data to non-defective blocks in the second storage block sets, and writes the dummy data to a storage block in the first storage block sets which corresponds to the defective block included in the second storage block set.