CAN智能节点间的数据通信.doc

CAN智能节点间的数据通信 摘 要 本课题设计对现场总线技术中CAN现场总线技术进行了分析和研究。CAN总线采用多主式工作方式，传感器或执行机构都是以智能终端的形式挂接在CAN总线的智能节点上，网络上任一节点均可在任意时刻主动地向其他节点发送信息，而不分主从。课题选取测控系统中的两个节点为主要研究对象，主要实现它们之间的数据通信。 课题研究的智能节点是以PHILIPS半导体公司的CAN总线控制器SJA1000、CAN总线驱动器82C250为主要核心器件，应用单片机AT89C51，具有高传输速率，高可靠性及强抗干扰性等特性。传输依靠CAN总线协议，将现场收集的数据信息上传到上位机，上位机将收到的信息进行进一步的处理反馈给执行机构，完成对现场设备高精度的实时控制操作。 设计主要包括节点的硬件设计和软件编写两大方面。硬件设计优化其结构，突出节点的实时性，高可靠性及抗干扰性，软件的编写是要确定控制算法、合适的软件结构和程序设计方法，实现节点的实时传输、错误检测等功能，以实现在总线中各节点之间的精确的数据通信。 关键词：CAN总线 AT89C51 控制器SJA1000 驱动器82C250 CAN 协议 Data Correspondence between the CAN Intelligent Notes ABSTRACT This paper attends to analyze and research the technology of CAN field bus. And Multi-Host is method the CAN field bus adopts. The sensors and the administrator are connected with the CAN bus intelligent note as the intelligent terminal. Any note on the network can send informations to other notes initiatively at any time, and there is no distinction of principal and subordinate. The aim of this paper is to choose two notes from the metrical system, and realize the data correspondence between them. The Controller SJA1000 from PHILIPS, and the Drivers 82C250 are the core apparatus in the paper, and the AT89C51 is used in this paper as well. By combining these three objects, a CAN bus intelligent note possesses the quality of high speed of transmission, high reliability and strong anti-jamming ability. Based on the CAN bus protocol, the data information collecting from the field is transmitted to the top computer, and then the top computer will dispose the informations it receives and feed back it to the administrator. In this way, the real-time control operation with high accuracy to the field equipment is finished. The hardware designing and the software compiling is the main task of the research. The hardware designing optimizes the frame of the hardware, and emphasis on the real-time and the high reliability and strong anti-jamming ability. The design of software aims to confi