摘要远程IO在工业领域应用广泛，在单一工控机控制系统中有时需要大量逻辑控制，而适合该系统的远程IO不多且存在一些问题。本文采用单片机采集数字量输入信号，通过以太网或RS-485接口将采集数据发送至上位机PC；上位机PC根据控制需要向单片机发送数字量输出数据由单片机控制数字量输出接口状态。46384
远程IO模块硬件部分主要包括三端光耦隔离传感器输入、开关量输入、拨码管输入、并行转串行扩展输入模块、STC12C5A32S2单片机最小系统模块、串行转并行输出模块、继电器输出、光耦隔离晶体管电平输出、W5500以太网模块、RS-485通信模块、电源模块、程序下载模块等电路。采用Keil软件进行输入扩展程序、输出扩展程序、W5500以太网通信等单片机程序设计；采用VC++6.0进行上位机程序设计。
上位机通过网络调试软件实现与单片机的通信，能够接收单片机定时发送的数字量输入数据；在需要时向单片机发送数据改变远程IO模块的数字量输出状态；并实现了用PC机同时与两块远程IO模块的通信。实验结果表明，该远程IO模块能够正常平稳运行、逻辑正确、可靠性高，可用于相应工业领域。
毕业论文关键词：远程IO；单片机；上位机；W5500以太网模块
 ABSTRACT Remote IO is widely used in industrial field. A single Industrial Personal Computer control system requires a lot of logic control. But just a little remote IO fits that system, and has some problems in practical application. In this paper, digital input(DI) signals were collected by the MCU. The DI data collected was sent to upper PC via Ethernet or RS-485 interface. The PC sent the digital output(DO) data according to the requirements of control. And the state of DO interface was controlled by MCU.
The remote IO module hardware part included some circuits, such as three terminal optocoupler isolation sensor input, switch input, dial input, parallel to serial expansion input module, STC12C5A32S2 MCU minimum system module, serial to parallel output module, relay output, optocoupler isolation triode output, W5500 Ethernet module, RS-485 communication module, power supply module, program download module. The MCU programs that contain the input expansion program, the output expansion program and W5500 Ethernet communication program was designed by the software Keil.  And the PC’s programs were designed by the software VC++6.0.
The PC realized communication with the MCU through the network debugging software, capable of receiving digital input data timing sent from MCU. The data which is from PC was sent to MCU according to the requirement or control to change the DO status. And the communication between one PC module and two remote IO modules was realized. The experimental results showed that the remote IO module can operate normally and stably, with high reliability. It can be used in the industry.
Key words: Remote IO; MCU; Upper PC; W5500 Ethernet module
 目  录
第一章    绪论    1
1.1课题研究背景    1
1.1.1工控机    1
1.1.2工控机控制方式    1
1.1.3 PLC逻辑控制    2
1.1.4问题的提出与课题研究内容    2
1.2研究现状以及发展    2
1.3单片机简介    3
1.3.1单片机概述    3
1.3.2发展历史    3
1.1.3发展趋势    3
1.4以太网及485通信    4
1.4.1以太网通信    4
1.4.2 RS-485通信    4
1.5远程IO模块    4
第二章  方案与硬件选型    5
2.1方案设计    5
2.2硬件选型    6
2.2.1数字量输入部分    6 基于单片机的远程IO模块设计+源程序+电路图:http://www.751com.cn/zidonghua/lunwen_48078.html