论文--基于CAN总线的交通信号控制节点设计.docVIP

摘 要 随着科学技术的快速发展,工业控制和生产自动化技术的不断进步以及微处理器的广泛应用，现场总线技术日益成为国内外各个行业的关注焦点。传统的独 立仪表已经不能满足目前控制系统大规模化、智能化、网络化方向发展的要求，一种新型的基于现场总线的智能仪表应运而生。CAN (Controller Area Network)现场总线作为一种自效支持分布式控制和实时控制的技术，以其稳定性好、可靠性高、抗干扰能力强、通讯速率快、维护成本低及其独特的设计，现己经成为国际上应用最为广泛的现场总线之一。 本课题采用主流单片机STC89C52为微处理器，结合独立CAN控制器SJA1000设计了CAN总线的数据通信系统硬件电路，使CAN总线的通讯更加直观。本文提出了相应的通信软件模型，通信软件模型包括应用层协议模块、基本通信模块和运动控制应用模块。具有现场交通信号控制、通行时间显示及CAN总线通信等功能可通过CAN总线与上位监控站和其他交通信号控制节点传送状态和各种参数，并接受来自监控站的控制信息以调整和改变自身的控制状态。 本课题设计的数据通信系统结构简单、使用方便、设计灵活，能够满足控制中网络化、智能化的发展要求，对目前基于CAN总线的研究具有积极作用。 关键词：CAN数据通信，,单片机 Abstract With the rapid development of science and technology, industrial control and automation technology continues to progress as well as the microprocessor application, field bus technology has increasingly become the focus of various domestic and international industry. The traditional independent instrument can not meet the current control system of large-scale, intelligent, networked direction requirements, a novel based on the field bus in intelligent instrument emerge as the times require. CAN ( Controller Area Network ) field bus as a self efficiency support distributed control and real-time control technology, with good stability, high reliability, strong anti interference ability, fast communication rate, low maintenance cost and its unique design, now has become the most widely used one of the field bus. The subject of the use of mainstream chip STC89C52microprocessor, with independent CAN controller SJA1000design of CAN bus data communication system hardware circuit, the CAN bus communication more intuitive. This paper presents the corresponding communication model, communication software model including the application layer protocol module, basic communication module and motion control application module. Among them, the application layer protocol module includes a message identifier allocation, data domain information format, data exchange mode and message filtering mechanism of content; basic commu