Research And Realization Of Intelligent Instrument Remote Transmission System Based On CAN Bus

With the economic development and continuous improvement of automation in the production management.The traditional instruments,fieldbus and Ethernet technology are combined to develop the field intelligent detection instrument with bus interface and remote monitoring system has become the hot spot in the industry.The research status of the subject at home and abroad was analyzed in detail,and a kind of remote transmission system of intelligent instrument based on CANBus was proposed in this paper.Firstly,the key issues where the problem lies were analyzed,and the overall design of the system was explained in this paper.Then the hardware and software design of the system were discussed in detail.The MCU C8051F040 was used as the core microprocessor of the intelligent instrument in the design.Besides,signal processing circuit,CAN Bus interface circuit and man-machine interactive interface,etc.were designed,and the water environment routine parameters such as temperature,pH, turbidity,conductivity,etc.were detected.The instrument was taken as the node of CAN bus and the detected data were transmitted to the bus by the CAN bus interface. The ARM7 processor LPC2292 chip of the Philips was used as the processor of the embedded CAN-Ethernet gateway,and the real-time operating system ofμC/OS-Ⅱwas transplanted on the hardware platform.The TCP/IP protocol stack was realized which was cut and suitable for the application of embedded systems,and the Web Server was built based on TCP/IP protocol,the gateway was taken as the host node of CAN bus and the received data were stored in it.Then the embedded Web Sever of CAN-Ethernet was accessed through IE browser by the staff in the monitoring center, and the real-time data detected by the intelligent instrument can be displayed on Web pages dynamically.The system performs steadily and efficiently in practical test.By analyzing the operation results and performance,the industrial Ethernet,CANBus and the intelligent instruments can be united to transmit the information of field intelligent equipments to the control room far away.The monitoring of some special or dangerous unattended places is realized,reducing the production accident rate to the lowest point.Moreover,the after-maintenance of equipments is simplified,bringing great economic profits for enterprises.Meanwhile,the system is an all-open system with strong portability,huge technological upgrading space and a good developing prospect.It can be easily applied to other monitoring areas such as national defense, military industry,marine geology and environmental ecology and so on.