| 摘要 |
PURPOSE:To make transmission work exact by rending the handshake situation to be monitored. CONSTITUTION:When transmission work is started, a read command is transmitted to a gate circuit 31, and the state signal from a receiver is fetched to discriminate whether or not the reception is possible. When the reception is possible, a write command is transmitted to a signal transmitting circuit 27 and data is transmitted. When the reception becomes impossible, the transmission is interrupted, and the read command is transmitted to a timer 29. Moreover counting is started, and a light emitting element 41 is caused to light up. The read command is again transmitted to the gate circuit 31 and the reception possible state is checked. When the reception is possible, the transmission is resumed, and the light emitting element 41 goes out. If the operation does not come to the reception state, the output of the timer 29 is fetched, and the investigation is made whether or not the reception failure reaches the reference time width. When the failure continues over the reference time width, the transmission work is interrupted. |
