| 摘要 |
PURPOSE:To improve data transmission efficiency by providing a means which resends reception unconfirmed data through another data link when a timer means enters a time-up state, and putting which is received in advance and data which is received by resending together and generating correct received data at a primary station. CONSTITUTION:A timer processing 9 controls a primary station monitoring timer 10 and a timer 4 for resending timing. Namely, both timers are started at the timer start request of a data link establishment/release processing part 6 when a data link is established, and if the primary station monitoring timer 10 enters a time-out state owing to a data link fault, a data link release request is sent to the processing part 6, and consequently the data link is released and a timer stop request is sent out, thereby stopping both timers. Further, even if one of the timers enters a time-out state, a resending request is sent to a transmission processing part 8 and data (frame) whose reception is not confirmed by the primary station is reset if found. |
