PURPOSE: To completely eliminate the oversight of an important part necessary for supervising by periodically changing an important displaying part, increasing an attention stirring effect, simultaneously, instructing a hard copy on a printout, and print-displaying the important displaying part.

CONSTITUTION: A process signal from a plant 1 is inputted to an input processing unit 3, it is stored into a process quantity storage device 4, when the displaying request of required information is executed, edit information is read from an edit information storage device 5b in a display control device 5 by using a display information editing device 5a, the information is edited along with a process quantity from the device 4, the information is outputted through a display information editing buffer 5c to a display information output device 5b, an edited result is converted to a video signal, etc., and the result is outputted to a display 6. The device is composed in such a way, and at present, at the time of stirring up the attention, one part of the display information is made into a displaying condition, outputted to a display information storage device 7, made conspicuous by changing a displaying luminance or by being blinked, and simultaneously, such a part is printed out.