PURPOSE: To call out the real measured operation data of the past shot at the time of the past molding operation on the display device of a machine as a graphic image at the arbitrary point of time desired by an operator.

CONSTITUTION: The real measured data stored in a buffer memory 14 is transmitted to the memory means 16 capable of storing many-shot data provided to a machine to be stored therein and the data stored in the memory means is subjected to conversion processing to be transmitted to a frame buffer.