CONTROL SYSTEM, AND PROXY SLAVE, PROXY MASTER, AND CONTROL METHOD USED FOR THE SAME

摘要

PROBLEM TO BE SOLVED: To make a control system operate even when communication quality of a network used for the control system is low.SOLUTION: A proxy slave 6 transfers a request from a master 3 that is a connection destination to a proxy communication network 5, and transfers a response to the request transmitted from the proxy communication network 5 to the master 3 that is the connection destination. A proxy master 1 transfers a response from a slave 7 that is a connection destination to the proxy communication network 5, and transfers a request transmitted from the proxy communication network 5 to the master 3 that is the connection destination. When the transfer cannot catch up a frame period specified by the master 3 or slave 7 because communication quality of the proxy communication network 5 is not guaranteed, the proxy master 1 and proxy slave 6 pretend that the frame has arrived to catch up the control period by adopting asynchronous communication.