下载后可任意编辑2024 届本科生毕业设计 分类号: TP273 题目:基于 PLC 和单片机通讯系统的设计与实现作 者 姓 名: ********* 学 号: *********** 系 (院): 机械与电子工程学院 专 业: 自动化 指导老师姓名: ********** 指导老师职称: 助教(硕士) 工程师 2024 年 5 月 10 日下载后可任意编辑摘 要PLC和单片机各有所长,PLC简单易用,控制程序可变,抗干扰性能强,并且具有较强的负载驱动能力,适用于各种恶劣的环境,可用作机械设备的主控制器件;单片机体积小,价格低,使用灵活,适用于家电、办公设备及传感器内部的核心器件,功能能强大。在实际应用中二者结合组成控制系统发挥各自的优势。要实现以上功能,关键要解决单片机与 PLC 之间的串行通信。本次设计主要介绍西门子 S7-200 系列 PLC 可编程控制器的自由口串行通信,以及利用单片机与 PLC 通信的方法。硬件以 89C51 单片机为核心,通过 RS-485总线与 PLC 通信,并介绍通信协议,以及软件的实现。通过 PLC 和单片机的通信仿真测试表明该通信系统具有一定的可靠性。关键词:PLC;自由口串行通信;单片机ABSTRACTPLC and MCU Each one has his good points., PLC is simple to use, control program variable, strong anti-interference ability, and has a load driven ability strong, suitable for a variety of harsh environment, can be used as the main control device of mechanical equipment;SCM small size, low price, flexible use, the core device is applicable to household appliances, office equipment and sensor, function powerful. In the practical application of the combination of the two control system to play their respective advantages. To realize the above functions, the key to solve the serial communication between SCM and PLC. Freeport serial communication in this design, mainly introduces Siemens S7-200series programmable logic controller PLC, and a method of using SCM and PLC communication.The hardware with 89C51 single chip 下载后可任意编辑as the core, through the RS-485 bus and PLC communication,...