Memory card device, and memory card control method for controlling the device

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 card address generation command used to request generation of a card address for identifying the memory card device, a card select command that includes a value generated from the card address as a bank identification number, and is used to switch an operation mode of the memory card device to a transfer mode that allows data transfer with the host apparatus, and a memory access command with a memory address of a specific bit width;
• a nonvolatile semiconductor memory which has 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 card address generation unit configured to generate the card address and transmit the card address to the host apparatus in response to the card address generation command;
• a bank identification number management unit configured to divide the storage area of the nonvolatile semiconductor memory into a plurality of banks and manage values generated from the card address as the bank identification numbers corresponding to the banks;
• a bank designation unit configured to designate one of the banks as an access target bank in accordance with the bank identification number included in the card select command;
• 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.

A method of controlling a memory card device which is detachably connected to a host apparatus, comprising:

• receiving 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;
• dividing a storage area of a nonvolatile semiconductor memory, which has 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, into a plurality of banks, and generating a plurality of bank identification numbers corresponding to the banks based on a card address used to identify the memory card device;
• designating one of the banks as an access target bank in accordance with a card select command which is transmitted from the host apparatus, the card select command including a value generated based on the card address as the bank identification number, and being used to switch an operation mode of the memory card device to a transfer mode that allows data transfer with the host apparatus;
• and
• accessing the one of the banks designated as the access target bank in accordance with the memory access command With the memory address of the specific bit width.