Study And Application About Formation Technology Of CAN/LIN Hybrid Network In Vehicle

Automobile electronics technology has been main power to push automobile technology go-ahead. Meanwhile, in vehicle a great number of electronics units demand a network connection in order to realize more intelligent control. Just like a nerve system "living" in vehicle, the in-vehicle networks have been convinced of its significance and it is absolutely necessary in a car. Recent years rapid growth of china automobile industry accelerate development of automobile electronics technology, so it is very significative to study in-vehicle networks.This paper mainly focuses on the study and application of in-vehicle communication based on a CAN/LIN hybrid network. To form an applied automobile network system and make it carried out in practice is the paper's final goal. Both CAN and LIN can be classified to field bus for the application of automotive middle or low control system, and the most important reason they are applied in vehicles is that they can integrate electronic control units into a whole. The CAN bus is the most widely used in cars and the LIN bus helps to optimize system cost and increases system efficiency. CAN and LIN don't compete with each other, but complement one another. The CAN and the LIN hybrid network will reduce the cost to great extent without affecting the performance of the whole system.After making a simple introduction to development of automobile electronics and in-vehicle networks, the paper above all analyze construction technology of CAN and LIN, including the analysis of characters and topology of them. Then the paper illustrates in detail how to design hardware and software of CAN/LIN gateway which is a pivotal part in the hybrid network. In the design of gateway a platform which is composed by a 32-bit CPU and a RTOS is adopted, and this solution caters to tendency of the design of automobile electronics. CAN communication API functions, LIN communication API function and functions which can exchange data between CAN and LIN are designed in the gateway to ensure a reliable and correct communication in the hybrid network. Test and analysis of the communication have been carried out, which can prove the connectivity of the hybrid network. When construction of the hybrid network is basically finished, it should been put into practice to prove its value. Therefore, the CAN/LIN hybrid network gets further study according to two designs of automobile electronic projects. One is the project of "An Automobile Tyre Pressure Monitoring System Base on CAN Bus", the other is the project of "An Automobile Climate Control System Controlled through a LIN Network". The design of network communications of the two projects is fulfilled by 8-bit MCUs, so there is much difference about the design from the gateway node. All above is got detailed depiction in the paper. Thus, all the design of corresponding part of the hybrid network which is composed by kinds of CAN nodes and kinds of LIN nodes is finally finished.Through the whole application, it is well considered on how to design hardware, software and both. One of most attractive features in the paper is the adoption of 32-bit CPU andμCOS-Ⅱin the design of the embedded CAN/LIN gateway. The well-done gateway can transmit data in real time, and through it information can share with different nodes which lie in both CAN bus and LIN bus. The two applications - "An Automobile Tyre Pressure Monitoring System Base on CAN Bus" and "An Automobile Climate Control System Controlled through a LIN Network" - are domestic innovations, and similar application is reported rarely in domestic journals. The paper illustrates the whole structure and communications of the two projects, and from another point of view, it is proved the feasibility of the CAN/LIN hybrid network in vehicle. This paper has the use for reference for domestic automobile company to independently develop the in-vehicle networks.