| 摘要 |
PROBLEM TO BE SOLVED: To operate as an on-line system even interruption of Ethernet by switching duplex communication lines of serial connection and Ethernet connection depending on the state thereof. SOLUTION: In an on-line semiconductor aligner 102 connected with an on-line control/supervision system comprising a host computer 101 according to a semiconductor substrate production system communication standard conforming to SEMI, a duplex communication line of a serial connection line 104 comprising an RS-232 and SECS-1 and an Ethernet connection line 103 comprising a TCP/IP and HSMS is employed. The two communication lines 103, 104 detect the state of communication line of semiconductor aligner 102 and switches the communication line depending on the detected state. |
