【作者】 陈卫国；

【导师】 戴瑜兴；

【作者基本信息】 湖南大学 ， 电路与系统， 2007， 硕士

【摘要】 视频监控系统在我国有非常广泛的应用,视频监控系统数字控制模块是一个重要的研究领域,本文针对基于CAN总线的数字控制系统的关键技术进行专题研究。(1)给出了一种由89C51单片机控制的简单易行的交流云台转动变速控制电路,实现了云台及其电动三可变镜头的控制;(2)给出了无需外加A/D、单线通信的防护罩自动温度控制电路,完成了单片机温度控制软件的设计;(3)提出了“无抖动”视频切换的设计思想,给出了16×8的视频切换电路,利用单片机在视频信号的场消隐期控制切换,从而实现了“无抖动”切换;(4)给出了一种三线接口通信的液晶显示实时时钟电路,完成了程序设计;(5)提出了在视频监控系统数字控制模块中,用CAN总线取代传统的RS-485总线,实现PELCO-P协议传输的方案。设计了视频切换主机和解码器的CAN节点通信电路,完成了SJA1000初始化、数据发送及接收的程序设计;(6)完成了以89C51单片机为微处理器的自动温度控制系统Proteus软件仿真;完成了以89C51单片机为微处理器的实时时钟系统Proteus软件仿真;(7)完成CAN通信模块的实物测试。系统分为矩阵、解码器和CAN通信模块三个部分,通过现有的视频监控系统数字控制模块关键技术的研究与改进,可以提高数字控制系统通信的可靠性和实时性,可以为原系统增加新的控制手段,或使原有的控制性能得到提高,这些技术,可以为视频矩阵、解码器、DVR、多媒体远程监控系统等产品设计提供参考。更多还原

【Abstract】 The video monitoring system is widely used in our country. The research on digitized control technologies of video monitoring system and its applications turns out to be an important research subject. This paper precisely conducts the special topic research in view of some important technologies of the digitized control module.(1) AC motor control circuit of PAN/TILT is designed ,which speed is controlled by AT89C51 MCU. DC motor control circuit of LENS is designed too.(2) The hardware and software of automatic temperature control is designed, which used in camera protect box without A/D IC. A kind of single wire communication IC is used in the circuit. So, the program is given.(3) A method of video switch without picture shock is discussed in this paper, and 16x8 video switch circuit is designed. AT89C51 can carry out time sequence logical control with the sync signals by request..(4) The module of real-time clock is designed, in which, LCM is used, a kind of three-wire communication IC is used too.(5) CAN-bus is used in digitized control module of video monitoring system, replace of RS-485. As a result, the control of the rotation of several pan-tilt-zooms based on PELCO-P protoco1 is realized.(6) Simulation of Automatic temperature control system and real-time clock system using AT89C51 as micro processors is realized.(7) Test of CAN-bus node is finished.The system in this paper is compartmentalized to be three parts: Matrix Switcher, Terminal Decoder and CAN communication system, by research of new technologies, communication ability, credibility, agility, reliability is improved, adding new function, the result can be consulted in the design of product such as Matrix Switcher, Terminal Decoder DVR, Remote Video Monitoring System.更多还原