A manner of reducing the power consumption is utilized in a tablet terminal equipped with a digitizer for inputting with an electronic pen. When another tablet terminal or a smartphone approaches the tablet terminal, each digitizer detects input. When the digitizer detects the input, it is determined whether the input is electronic pen input from the electronic pen or proximity input caused by the proximity of the other tablet terminal or the smartphone. In the case of electronic pen input, coordinate information is transferred to a system, while in the case of proximity input, the system takes an action such as shifting a tablet terminal to a sleep state.