DATA COMMUNICATION NETWORK SYSTEM

摘要

A data communication network system which allows a desired unit to choose the start point of a communication transmission schedule. The data communication network system comprises a plurality of electronic control units which perform network communication through communication lines, in accordance with a time triggered communication protocol. The data communication network system is provided with a control means for setting the communication lines into a communication prohibited state in advance and releasing the communication prohibited state at predetermined timings. One predetermined unit among the plurality of electronic control units transmits a synchronization message for matching the communication timing with another unit immediately after the communication prohibited state is released.