Patent attributes
The data processing unit uses, for predetermined information processing, a series of data read by uniformly accessing a predetermined address range of the external storage device through the external interface. The determination unit determines whether to write the data read from the external storage device by the data processing unit to the internal storage unit or not and writes, to the internal storage unit, data determined to be written to the internal storage unit. When again reading data within the same address range of the external storage device, the data processing unit alternatively reads data from the internal storage unit.