PURPOSE: To execute counting to make it practical and convenient by providing not only a writing input function of a character but also a counting function, and only pressing the character, etc. by the tip of a writing tool.

CONSTITUTION: When a desired character is written and inputted by a writing tool 1, resistance value of pressure sensible rubbers 8aW8c is varied. A detecting circuit 13 detects this state, and outputs detecting output signals T1WT3. This output signal is sent to a pulse detecting circuit 16 to input to an interruption input terminal INTI of a CPU15, to execute the interruption input processing, to form a character pattern, also, in case of a counting mode, the counting operation is executed. In case of designating the counting mode, inverse Δ, M and Δ symbol are written and inputted, and thereafter, pressure is put on one optional direction to the tip of the writing tool 1 to display the counting of a slip, etc., the total of its value and the total sum.