| 摘要 |
<p>PROBLEM TO BE SOLVED: To deal with the variation in state in real time by reducing communication data quantity in a monitoring method of polling selecting system for monitoring state of plural target equipments by one control and monitor device. SOLUTION: A control monitoring device 1 sequentially questions target equipment 21, 22,..., 2j,..., 2n whether states are changed or not. The respective target equipment 2j return responses showing that there is no change when the state is not changed as compared to previous response time. Then, a signal containing real data showing the state after the change is returned when the state is changed compared to previous response time. Since real data showing the state of the target equipment is not contained in the signal returned when the state is not changed, communication data quantity can be reduced. It is especially effective when the target equipment is an acoustic equipment.</p> |
