To eliminate the need for an external power source without occupying a large installation space by reading current date data and storing them in respective areas of a storage means in order together with state discrimination data each time an input means is operated.

When an administrator operates a PRINT button of a console panel 2, a switch 9A is turned ON on receiving a command from a CPU 5 and only for the period, the electric power is supplied from an internal power unit 8. Then various data such as individual discrimination data, state discrimination data, date data, and time data stored in a memory 4 are rearranged by employees, etc., and laid out in an easy-to-see state, so that they are printed on an internal form. When an individual button of the console panel 2 is operated, a switch 9B is turned on on receiving a command from the CPU 5 and a display 7 is supplied with the electric power from the internal power unit 8. Then the time data that the CPU 5 reads out of an RTC 3 are displayed on the display 7.