文档介绍：摘要
火灾作为危害人类生存的大敌,越来越受到人们的重视。随着高层建筑的不断增多, 火灾隐患增加。一旦发生火灾,将对人的生命财产造成极大的危害,会给国家造成极大的经济损失,给社会带来重大影响。所以,如何较快的检测到火灾越来越受到人们的重视,各个国家在这方面都投入的巨大的人力和物力,各种各样的火灾检测及报警系统便应运而生了。
本系统根据火灾发生时的特征即烟和热,利用QM-N5传感器检测烟雾,利用DS18B20检测温度,当检测到烟雾或温度较高时,通过单片机处理实现报警,并通过MAX485实现与上位机通信,实现上位机对下位机的分布式监控。
本系统下位机有信号采集模块,报警模块,串口通信模块组成,上位机通过VB界面对下位机进行监控。整个系统效果还是比较好的,反应也较快,测量结果比较准确,有一定的实用性和应用前景。
关键词:传感器;MAX485;上位机;下位机;分布式
Abstract
As the great enemy of mankind's survival,the fire are getting more and more attention With the continuous increase in high-rise building, the hidden trouble of fire increased. Once a fire happened ,there will be a great harm to people's lives and property ,it will cause great economic losses and a major impact on ,how to konw quikely when the fire happens are receiving more and more people's attention,and every country are putting more and more people and money on this ,a wide rang of fire detection and alarm system came into being.
According to the characteristics of a happenning fire ,namely the heat and smoke,the system in this paper make use of QM-N5 smoke detection sensors to detect the smoke,make use of DS18B20 to test the heat,when the system find the smoke or high temperature,handling by the SCM,the system will give an municate with the PC through MAX485,so that the PC can control the SCM.
The system are made up of signal acquisition module, alarm modules, munication PC monitor the SCM through VB final effect of the entire system is relatively good, and has the faster response the measurement is paratively accurate, it still has a certain relevance and application prospects.
Key words: sensor; MAX485; PC; the next crew
目
录
引言 1
1 课题的现状及研究意义 2
课题现状 2
课题的研究意义 2
课题要求和各章内容安排 2
2 相关技术和基础理论介绍 3
传感器概述 3
RS—485总线 4
4
RS -485 方式构成的多机通信 5
主要器件及应用 6
6
-N5 9
MAX485 10
STC89C51 12
3 系统的总体分析与器件的选择 16
系统的整体框架 16