Communication network system having high-ranking network and low-ranking networks, interchange terminal connecting high-ranking network and low-ranking network, microcomputer controlling connection between transmission line of low-ranking network and transmission line of high-ranking network, and communication transmitter-receiver connected with transmission line of low-ranking network and transmission line of high-ranking network

摘要

A communication network system has a host network and low-ranking networks connected with the host network through respective interchange terminals. Terminals containing the interchange terminals in the host network perform communication based on FlexRay. FlexRay sets a static segment and a dynamic segment every communication period. Communication zones are fixedly allocated to the respective terminals in each static segment. Communication zones are changeably allocated to the respective terminals in each dynamic segment. Terminals of each low-ranking network perform communication based on LIN or CAN protocol. The interchange terminals connect a transmission line of the host network with transmission lines of the low-ranking networks during the transmission period of each dynamic segment, so that each terminal of each low-ranking network can perform communication based on LIN or CAN protocol with the terminals of the other low-ranking networks through the high-ranking network without any protocol conversion.