Construction Machinery Intelligent Control Ethernet CAN Bus Converter Design

In recent years, with the rapid development of communications technology, network technology and the control technology, profound changes happen in industrial control field. Controller Area Network is widely used in industrial production process because of the characteristics of real-time, reliability and distributed, but it is not suitable for long distance transmission. Ethernet had a tremendous development since it came into being, and became the current mainstream technology of remote data transmission, and the transmission has the characteristics of high-speed and long-distance. The subject is 863 Project"Construction Machinery Intelligent Controller". The programming environment of the Programmable Logic Controller is the MULTIPROG which uses Ethernet to download and debug by default, but The Controller needs to download through Can-bus. In the case, in order to realize the interconnection of heterogeneous networks Ethernet and Can-bus, and make the Personal Computer communicate with the Controller, this paper propose a design for the converter to connect the Ethernet and the Can-bus.At first this paper studies the work of the Ethernet and the Can-bus, the Embedded Real-Time Operation System uC/OS-II and the transplantation of the uC/OS-II, then analyzed the delay characteristics of the converter, and proposed a split-assembly algorithm between Ethernet packet and Can-bus frame and queue management mechanism according to the main delay factors for the converter, and proposed the functions for the converter and the interconnect model between the Ethernet and the Can-bus, at last, used the ARM9-based microcontroller STR912 as the hardware platform and the Embedded Real-Time Operation System uC/OS-II as the software platform, and designed the protocol conversion algorithm between the Ethernet and the Can-bus and the communication program of the Ethernet and the Can-bus, especially, the Can-bus communication program established the data channel by circular queue cache and used the queue management mechanism to manage the Can-bus queue buffer, realized the Ethernet Can-bus converter. Experiments show: the converter can transmit data real-time between Personal Computer and controller.