Research Of Embedded PC Control System Based On High-Speed Smart Fieldbus

Aiming at the shortage of the present control system at the industry scene, an embedded PC control system based on fieldbus is presented. This system has high-speed smart communication ability, and it is so small that the system can be embedded in industrial equipment.Firstly, by analyzing the evolution of control system, this paper introduces a variety of fieldbuses and embedded PCs, which appear with the development of microelectronics and personal computer. In the system, CAN bus is used as fieldbus and PC/104 computer as the control computer.Secondly, the control system centering CAN bus and PC/104 is realized. The CAN communication adapter of PC/104, the network model and communication protocol of CAN bus are explained briefly. In the design of the hardwares, the CPLD is used in the adapter, instead of the discrete devices, to reduce the circuits' area and power. Moreover the system on chip (SoC) integrated with high-speed microprocessor and CAN controller is applied to complete the operation of CAN bus, and the circuit of photoelectric isolation enhances the ability of anti-jamming. Using WinDriver, the Windows device driver of the adapter is developed. To obtain the easy application, the driver is encapsulated as an ActiveX control. The network model is built on the Reference Model of the Open System Interconnection (OSI/RM) proposed by the International StandardizationOrganization (ISO), and the protocol of application layer in the model is defined.Finally, the paper gives an example of the system used in the automatically spinning control system in the machine. Many essential parameters were tested, which includes communication speed, the percentage of errorness or lost packet, and the response time etc. All prove that the system has very good performance and great value in application.