| 摘要 |
PURPOSE:To perform error recovery on an HDLC basis without using timer control, etc., and transmit plural selective reject (SREJ) frames without waiting for a resent I frame to arrive by using a queue which is controlled according to the transmission of SREJ frames and the reception of the resent I frame. CONSTITUTION:When the invented device is installed at a reception side, a control circuit 11 generates an SREJ frame having the transmission sequence number of an information I frame as a reception sequence number unless the I frame is received normally, and the number N(R) is set in the queue in a queue control circuit 12. Then, the SREJ frame is sent from a circuit 6. Then when the resent I frame is inputted from a transmission side, a control circuit 11 judges the coincidence of the transmission sequence number N(S) with the number stored at the head of the queue. When the coincidence is obtained, the number is queued out and inputted to a reception I frame order control circuit 8. When not, an SREJ frame having the number Q1 at the head of the queue as the number N(R) is resent. Then, the number at the head of the queue is queued out and Q1 is taken out. |
