PURPOSE: To perform use by the discretion of a computer user at all times by generating output in response to an application program during execution and generating and displaying a simulation keyboard independently of the application program during the execution.

CONSTITUTION: The simultaion keyboard whose whole body is indicated by' K is plotted on an output screen 28. When pressure is applied onto a contact sheet by a finger, a stylus or the other object, the contact sheet is brought into electric contact with resistant coating. During use, a touch screen controller 18 impresses a voltage gradient in the directions of 'X' (horizontal direction) and 'Y' (vertical direction) across the resistant coating. By establishing a voltage divider circuit, a touch forms a voltage signal detectable by the touch screen controller 18 and the signal indicates an average orthogonal coordinate taken in the directions X and Y in the touch area of a screen. Thus, use is performed by the discretion of the user.