| 摘要 |
<p>To control a plurality of apparatuses (6a-6z), the apparatuses and a master control unit (2) having a communication unit are all connected for intercommunication in series through communication lines (10). One of the communication unit is used for exchanging messages between the master control unit and the apparatuses. Messages can transfer from one apparatus to another one in sequence. In another embodiment, the last apparatus is further connected with another communication unit of the master control unit, making a looped communication circuit. Therefore, messages sent out from one of the communication units of the master control unit can be received by the other communication unit to monitor the intercommunication. If a communication line is disconnected, messages can be also sent from another communication unit of the master control unit in reverse direction, making it possible to communicate with all of the apparatuses.</p> |
