Controlling access to redundant transmission channels in bus system

摘要

The sending subscriber (6 or 7) transmits a message simultaneously over two channels (a,b) via separate lines (8,9), and receives on two other lines (10,11;12,13) for evaluation of starting and check symbols. The receiving subscriber monitors the correct transmission of several messages and forms a comparison value for the security of transmission on each channel. In accordance with the comparison values the more propitious channel is chosen for reception. A counter is incremented by each correctly recognised starting and check symbol on one channel, and decremented by each correct symbol on the other.