Network Based On The Can Bus Temperature Measuring Instrument Management And Control System Development

With the emergence and development of instrumentation bus technology, fieldbus in the control apparatus, production process, and other fields have been playing an increasingly important role. CAN fieldbus as an effective distributed control and real-time control of the technology, with good stability, high reliability, anti-interference capability, high-speed communications, low maintenance costs and its unique design is attracting increasing attention and is recognized as one of the most promising fieldbus. With the rapid development of fieldbus technology, traditional automatic instrument is seriously challenged, and will be replaced by the open fieldbus instruments. Instrument research and development based on the agreement of CAN is of great practical significance.To meet the needs of science and technology, the paper studies in a wide range of literature, and developes a standard measurement instrument for the management and control system based on CAN standards to implement the Intelligent Instrumentation Bus. Among others, with the consistent CAN communication protocol, bus instrumentation realizes the meter signal conversion between the unities which makes more open and versatile.In this paper, a detailed analysis based on the design of the CAN protocol of intelligent instrument is given as well as design features. According to functional needs and hardware design, selection AT89C52 and SJA1000 CAN controller chip as a specific hardware circuit, use Keil C51 and assembly languages to develope system architecture and software modules and use VB to program for the host computer. Finally, problems on anti-interference when running system are issued in a detail.Proven by practice, the system achieved the Intelligent Instrumentation's basic function of the parameters of real-time data acquisition and real-time data transmission, which is very practical and effective. Compared to the conventional instruments, instrument based on the CAN fieldbus is better in fault-tolerant processing, data exchange, system management anti-interference and so on.