PURPOSE: To simplify the constitution of a circuit relating to detection and to reduce also a factor of a fault or the like by detecting a contact position directly from each electrode.

CONSTITUTION: In accordance with a signal outputted from a scanning signal generating part 21a, 5V DC voltage is impressed to respective electrodes 2-1W2-8 at a prescribed timing. If an area A is depressed and electric contact is generated between the electrode 2-8 and an electrode 2'-8 during the scanning of the electrode 2-8, voltage impressed to the electrode 2-8 is led into the electrode 2'-8 and an input voltage to an input terminal Q8 of an electrode detecting part 21b goes to a prescribed voltage value or more, so that a detecting part 21b sends a detecting signal to a coordinate deciding part 21c. The deciding part 21c decides the position of the A on the basis of a scanning signal outputted from the generating part 21a and a Q8 detecting signal outputted from the detecting part 21b and sends a signal with a prescribed RS232c standard from a conversion circuit 24.