JPH0517754B

PURPOSE:To execute a condition restoration accompanied by the replacement of switch only by means of the operation of a switch at a video switch side to execute the replacement simply by storing tally information in an interface and controlling the said switching device based on storing data with the requesting signal of the switch. CONSTITUTION:A selecting control is executed from a control input terminal 12 through an interface 11 by control circuits 13 of respective switch, and the tally is returned to the interface 11. A data processing is executed by a data processing part 15, the control and the fetching of the tally are executed through an I/O between respective switch, and the tally information is stored in a data memory 17. When a switch 7 for control request is operated, the requesting signal and the address of the switch are sent to an I/O part 16 of the interface 11, the interface 11 fetches the said information from the data memory 17, a video switch 8 of a requesting source is controlled through the I/O part, and the condition before the replacement can be restored.