Method and system for parallel transmitting serial data according to high level data link control

Abstract

The invention can effectively reduces the occupation on redundancy bandwidth, avoid the generation of flag bit sequence of segments and lower the load of CPU. In the invention, reading the k bits of next group to the shift register from serial HDLC data stream; if the valid data only have C bits, C<K, then the front K-C bits in flag bit sequence are filled into the remaining space of shift register; sending the data in the shift register, and recording C; when needing to send next HDLC frame, the rear K-C+A bits in flag bit sequence are filled into the shift register, and then reading the valid data of the next HDLC frame from the serial HDLC data stream; wherein, A represents the bit numbers in flag bit sequence.

Description

technical field [0001] The invention relates to the communication field, in particular to the parallel transmission technology of serial data in the advanced data link control protocol. Background technique [0002] High-Level Data Link Control Protocol (High-Level Data Link Control, referred to as "HDLC") is defined by the International Standardization Organization (International Standardization Organization, referred to as "ISO"), which is a general term for bit-oriented data link protocols. Protocols mostly use HDLC or some subset of it. [0003] HDLC is bit-oriented, in other words, data is monitored bit by bit. The transmission content consists of binary data without any special control codes, but the information in the frame contains some control and response commands. HDLC supports full-duplex transmission. Full-duplex means that data is transmitted in two directions at the same time, which can generate higher throughput. [0004] HDLC is suitable for point-to-poin...

AI Technical Summary

Problems solved by technology

[0018] In practical applications, there are the following problems: through the existing serial-to-parallel transmission method, for point-to-multipoint connections, there may be a large amount of redundant bandwidth, and there are fragmented FLAGs in the transmitted parallel packets, which increases the burden on the receiving end

When the master node sends serial data to slave node 1, it will replace the data belonging to slave node 2 in the serial data with FLAG. Since the serial HDLC data has been encoded by inserting 0, the data that needs to be replaced is not necessarily FLAG Integer multiples of the fragmented FLAG may be generated after the replacement. After the master node divides the fragmented serial data stream into parallel data packets and transmits them to the slave node 1, these fragmented FLAGs will interfere with the receiver. The slave node 1 needs to modify the fragmented FLAG Judging and processing increases the burden on the slave node, and in the process, a large number of idle FLAGs are transmitted, which takes up a large amount of bandwidth. For slave nodes 1 and 2, only half of the transmitted HDLC data is all The effective bandwidth is reduced, the redundant bandwidth is increased, and the utilization rate of resources is low.

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