Patent ID: 7185146

Claim:
A memory card device which is detachably connected to a host apparatus, comprising: a host interface unit configured to communicate with the host apparatus and receive a plurality of commands from the host apparatus, the commands including at least a memory access command with a memory address of a specific bit width; a nonvolatile semiconductor memory which includes a storage area whose memory size is larger than a maximum memory size that is addressable by the memory address of the specific bit width; a bank identification number management unit configured to divide the storage area of the nonvolatile semiconductor memory into a plurality of banks and manage a plurality of bank identification numbers corresponding to the banks; a bank designation unit configured to designate one of the banks in accordance with a bank identification number included in a bank designation command transmitted from the host apparatus; and a memory control unit configured to access the designated one of the banks in accordance with the memory access command with the memory address of the specific bit width.