PURPOSE: To perform specified operation quickly at the stop and recovery of data from a central computer, by adding a device monitoring information from the central computer for a terminal computer and switching a program when the information is in pause.

CONSTITUTION: A central computer finally transmits a series of information consisting of operation instructions to a terminal computer synchronizingly. The terminal computer stores this information to an information storage device 17 via a buffer 5 and transmits the information to a coincidence detector 7. When the device 7 detects an output from the buffer 5 and a fixed buffer 6 in which the same information as the instruction from the center, the device 7 resets a counter device 8 and selects a normal use program 18 via an address selector 10. An operation device 15 reads out information stored in a device 17 and outputs the information through operation. When the information from the central computer is stopped, the device 8 is not reset, the device 10 selects an emergency program 19 with the output and the device 15 outputs a signal stopping the control variable. When the information from the center is restored, the signal of the device 7 selects a normal use program for the device 10.