In a storage device having a redundancy remedy function in a block unit having a memory cells array divided in plural blocks, prior to the access operation to individual memory cells in the block, the block address BA for specifying a block is entered, and block redundancy is determined in the entered block address BA, and hence it is not necessary to determine input or redundancy of the block address BA on every occasion of the access operation. As a result, the time to the access operation start to the memory cell can be shortened, and the access speed is enhanced.