A device and a method are provided for increasing processing speed and for ensuring system security when an application or a driver is added. The device includes a first CPU group 10A that executes software 20A composed of basic processing 22 and an OS 21A; a second CPU group 10B that executes software 20B composed of additional processing 23 and OS 21B corresponding to the additional processing, inter-processor communication means 40 1 and 40 2 used for communication between the first CPU 10A and the second CPU 10B, and access control means 30 that controls access made by the second CPU 10B to a memory 50 and/or an input/output device 60.