Research And Design Of In-Vehicle Network Communication Software Based On CAN-Bus

Modern cars are of many complex electronics equipments. These equipments are connected into a network by bus protocol. Byt this way, we can use of resources and share data effectively. The network provides a uniform data exchange channels for electronic devices and controllers within the In-vehicle. In-vehicle network has became the mainstream technology basis of automobile manufacturers.The key technologies of in-vehicle network which are used for improving the reliability of communication between controllers and reducing the cost of wires is including CAN, LIN, FlexRey, MOST, IDB1394 etc. Comparison of these buses, based on the principle of design simple, low cost, low-speed and high-speed communications requirements, CAN bus is the preferred. For the automobile factories, CAN network design is the key to CAN network commucation. Throughout the current design techniques, they can be divided into two categories. One is based on simulation and test-based traditional design methods, and the other is based on protocol design-based approach. Traditional approach puts the requirements of each node's agreement together, through simulating and testing means to check the correctness of the agreement, and get the right communication protocol. New approach through the system design technology, with theoretical method for time series modling, analysis and design system commucation protocol, to ensure system real-time performance and correctness of the protocol, and finally release the correct protocol.This main task of this paper is to use principles of protocol design methods, research and realizate the in-vehicle network communication software based on CAN-bus. For this purpose, firstly, this paper analyzes the CAN protocol. CAN protocol is a arear bus protocol. This paper focuses on researching the protocol characteristics, hierachical structure and compare with the ISO/OSI basic reference modele.The paper dscribes 4 frame types, their uses, frame structures. This paper also made a thorough study on bus arbitration, frame priority identification and so on. Secondly, it analyzes the MSCAN module, focusing on the MSCAN Structure, characteristics and working principle. Then design system architecture by using the hierarchical design method, and complete the functions layer by layer. At last, integratie the layers'functions and design the test cases to verify the system functionality and reliability.