| 摘要 |
PURPOSE:To improve serviceability to and reliability of subordinate stations by connecting a master station to subordinate stations via several circuits provided. CONSTITUTION:Circuits LL1 to LLn from master station KS, provided, can all be connected to subordinate stations SS1, SS2 by way of branch unit groups BR1, BR2 and interfaces IF1, IF2 respectively. Then, each interface is equipped with switches as many as circuits and a subordinate station polled from the master station control a corresponding switch to start communication with the master station. |
