【毕业论文 毕业设计】基于单片机的环境温湿度检测系统.doc

摘要
环境温湿度检测系统是日常生活、工业生产和农业管理中广泛使用的一种设备。该设备具备以下主要功能:实时检测出环境中的温度和湿度参数值,并显示出来,根据设定的报警限予以报警指示,可以和上层控制器通信。
随着单片机的大规模应用,单片机在检测系统中也越来越多的被使用。本设计以AT89S52这款低功耗、高性能、在系统编程的8位单片机为系统控制处理核心,由单总线数字温湿度传感器DHT11、数码管显示屏、LED与蜂鸣器、通信串口和按键控制输入等五个部分组成,从而实现环境问世的监测系统的主要功能。后期的探索设计——换用红外遥控控制和LCM为显示屏、外加时钟和存储芯片、增加照度检测电路,极大地提升了系统的性能,使系统不仅可以检测并显示环境温度、湿度和照度变量,而且可以按照时间顺序存储适量的数据。
此外,系统有降压整流和稳压滤波电路,可用交流市电(220V)、各种安全直流电(5~24V)、太阳能电池等为系统供电,并且可以存储少量电能(900mAh),因此,系统有较宽的工作电压,可满足多种应用场合。
本设计由Protel画出了电路原理图和PCB图,并由此完成了硬件的制作,使用C51语言对单片机进行编程控制,并模块化仿真,最后通过综合调试,符合预期的设计要求。
关键词:AT89S52单片机 DHT11传感器 PCB设计温湿度检测
Abstract
Environment temperature and humidity detection system is a kind of equipment which is widely used in daily life, industrial production and agricultural equipment has following main function:detecting the temperature and humidityparameters in the environment real-time and display them,giving alarm indication according to the set limits, and being able to contact with upper controller.
With the SCM used large-scalely,the SCM is more and more used in detection design,uses the 8-bit SCM named AT89S52,which has a lot of advantages such as low-power dissipation,high-performance and ISP,and made up of five parts:single-wire digital temperature and humidity sensor,digitron display,LED andbuzzer, unications and keys input,thus perform the function of environment temperature and humidity detection exploration design in later stage,including infrared remote control and LCM display,clock and memory chips,and illumination detection circuit,immensely promotes the property of the system,makes it not only detecte and display the temerature,humidity and illumination,but also store some data in order of time.
In addition,with step-down rectifier and stabilivolt filter circuit,the system can use utility power AC220V,different safety DC5~24V,solar battery to supply power,and store some electric energy about 900mAh,so that it has a wide power supply voltage and meets diffe