毕业设计：基于RS485的温湿度数据集中处理和显示单元硬件设计.docVIP

基于RS485的温湿度数据集中处理和显示单元硬件设计 电子信息工程专业 唐金龙 [摘 要]本课题设计的是一套计算机控制的温度、湿度实时监测与报警系统，可应用于多种需要采集温湿度数据的场合，该系统主要由温湿度数据采集单元、数据的传输和温湿度数据的集中显示和处理三部分组成，本文完成了整个系统温湿度数据采集单元的硬件设计。 系统采用数字式温湿度传感器和RS485传输网络的设计思想。其中每个温湿度传感器由一个数据采集单元控制，每台数据采集单元负责一定区域内的温湿度监测。数据采集单元的核心部件为单片机，主要完成对其所连接传感器件的测量与控制以及与主机的通信等功能。各采集单元以网络结点的方式挂接到RS485传输网络上，传输距离远，还可有效的抑制共模干扰。设计中的RS232/RS458转换器用来实现RS485总线网络与主机RS232串口通信的相互转换。系统中为主机与各采集单元之间的数据通信制定了完备的通信协议，以保证通信的可靠性。 [关键词] RS232/RS458；单片机；数据采集；通信协议 The Hardware Design of the Temperature and Humidity Data Processing and Display Unit Based on RS485 Electronic information Engineering Major　TANG　Jin－long Abstract：This paper introduces a kind of real-time monitoring system for temperature and humidity controlled by computer,which is can be used for many applications. The system mainly consisted of temperature and humidity data acquisition unit, the data transmission and temperature data display, this paper has completed the hardware design of the temperature and humidity data acquisition system. The system adopts digital temperature and humidity sensors and RS485 transmission net technique. Each temperature and humidity sensor by a data terminal control.Each data collector is responsible for a region.The kernel of data collector is MCU,which takes charge of measurement,control and communication with the host controller.The RS485 transmission net is made up of the data collection station,which can transmit for remote distance and restrain common mode interference.The RS232/RS485 converter is used for conversion between RS485 and RS232,which is used by the host controller,computer.A self-contained serial communication protocol is defined,which can help the host controller communicate with the data collector. guarantee the dependability in the communication. Key words：RS232/RS485；MCU Data collection； Communication Protocol 目 录 1 引言 ....................................................................1 1.1 课题研究的目的和意义 1 1.2 温度、湿度数据采集与监测技术的发展历程 1 1.3 温度监测与报警系统的组成 2 1.3.1 温湿度数据采集