VALUE EQUALIZATION DEVICE FOR CONSTANT-PERIOD GATHERED DATA

摘要

PROBLEM TO BE SOLVED: To lighten the load by facilitating the data equalization of a control system having duplexed process data bases. SOLUTION: An absent data counter is provided for a file of process data with time which are transmitted at a constant period and this counter is updated sequentially unless process data can be received (steps S11 and S17); when the update of the absent data counter is detected (steps S13 and S14), equalization to data in a master-side data base is performed to eliminate the need to monitor the system state, thereby lightening the load of the equalization.