To use a control board in a long life cycle without deteriorating functions or spec by enabling an NAND type flash memory controller to correspond to various NAND type flash memories.

A main CPU is started by turning on a system power source, and an NAND type flash memory controller 12 is started. In starting the NAND flash memory controller 12, an NAND ID 20 is read from the NAND type flash memory 13, and individual specifications necessary for memory access are set, and configuration data 21 are read, and a speed (access time) when memory access is set. Then, user data 22 of the NAND type flash memory 13 are copied to a DRAM, and a main program is executed by the main CPU.