摘要 |
PURPOSE:To prevent the transmission of an erroneous signal by bringing the level of a specific edge connector of an input/output module of an optical multiplex transmitter into logical H and detecting the potential of a specific bus on a mother board on the other hand so as to detect the presence of the module on the mother board. CONSTITUTION:When a certain module 2 is assembled to a connector T1, i.e., the mother board 5, the level of a terminal t1 of the connector T1, i.e., the bus A obtains logical H. If the module is not assembled conversely, the level of the terminal t1 of the connector T1, i.e., the bus A obtains logical L. Further, a control module is fitted to the edge connector the same as other modules, the voltage of the bus A is checked in this state and only when the voltage exists, each input/output module is made possible for the operation. Thus, if the input/output module is not assembled to the mother board, the transmission is prevented by reading the state of the bus. |