PURPOSE: To provide the bit map display monitor by which a coordinate input device which can be used only in the window environment can be used in the console environment.

CONSTITUTION: A window system deciding means 13a decides the window environment or not, and by a decision result output means 16, its result is written in a register 6. A monitoring means 13 reads the value of the register 6 and switches interruption control from a mouse 11 in accordance with the window environment or not, and generates a request corresponding to the interruption to a central processing unit 4. Accordingly, even in the case of being not the window environment, the mouse 11 can be used independently from a keyboard, therefore, even when a keyboard input comes not to be recognized in the console environment, a release work can be executed by the mouse 11.