PURPOSE: To make it possible to perform a very good-operation efficiency process control by providing one-to-one correspondence between data input items and input parts on the displayed function screen and inputting data from a corresponding input part to a computer.

CONSTITUTION: Computer 1 which performs the process monitor control displays the state of the process on CRT display unit 2 consisting of control unit 3 and display part 4, and operation part 6 has the ten-key input part to input data to computer 1. Then, one-to-one correspondence is provided between input items of designated data and input parts on the function screen displayed on unit 2, and data is inputted from a corresponding input part to computer 1. As a result, input required items can be clarified for the function screen, and the input of needless items can be ignored, and only items of input miss can be inputted again from the ten-key at an input miss time, so that the process monitor can be performed with a very good operation efficiency.