【作者】 许操；

【导师】 周如培；

【作者基本信息】 西安理工大学 ， 微电子学与固体电子学， 2003， 硕士

【摘要】 本文针对目前工业现场控制系统存在的不足，提出了基于高速智能化现场总线的嵌入式PC控制系统，该系统具有高速、智能化的通讯能力和可以直接嵌入到工业设备中的小巧体积。 首先通过分析控制系统的发展趋势，简述了随微电子技术和个人计算机的发展而出现的各种现场总线和嵌入式计算机系统。随后确定在控制系统中使用CAN总线作为现场总线网络，使用嵌入式的PC／104主机作为控制计算机。 然后具体实现了该控制系统。主要包括PC／104总线的CAN适配器、CAN总线网络模型和通信协议的设计。在硬件设计上，通过使用可编程的CPLD器件取代体积和功耗都太大的传统数字电路，使用集成了MCU和CAN控制器的SoC芯片来完成CAN的主要操作，总线收发上利用光电隔离电路提高抗干扰性。CAN适配器的驱动设计借助了第三方的工具软件WinDriver，并将驱动封装为ActiveX控件以便于用户应用程序的调用。此外，还根据国际标准化组织(ISO)提出的开放系统互连参考模型(OSI／RM)建立了控制系统的网络模型，并且定义了模型中的应用层协议。 最后，说明了该系统在纺织机械自动清纱控制系统中的一个应用实 西安理工大学硕士学位论文例，并就这个应用实例，对系统的通讯速率、丢报率、出铅率以及响应时间等参数作了详细测试。测试表明系统具有极好的性能，能够在 100米左右的范围内挂接 100个以上的控制节点并以 500kbps的速率通信，系统响应时间小于 lins，出错率和丢包率均低于万分之一，囚此该系统在工业自动化中具有很大的应用价值。更多还原

【Abstract】 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.更多还原