摘 要：本设计把传感器和单片机作为火灾监控系统的中心器件，做出的火灾报警器可以实现大型建筑的火警监控及报警功能。单片机采用STC89C52，它拥有灵巧的8位CPU，能够为众多嵌入式控制应用系统提供高灵活、超有效的解决方案。传感器选用MQ-2型半导体可燃气体敏锐元件烟雾传感器，完成烟雾的检测。当传感器所处环境中存在烟雾气体时，传感器的电导率随空气中烟雾气体浓度的增加而增大。选用DSl8B20温度传感器完成温度的检测，与传统的热敏电阻相比，它能够直接读出被测温度并且可根据要求通过简单编程实现9～l2位的数字直读方式。该系统设计成本较低、可靠性高、电路设计简单，可广泛应用于所有建筑的火灾监控。65387

毕业论文关键字：火灾报警器，单片机，传感器

Abstract：This design used the sensor and microcontroller as the center device of the fire monitoring system, and the fire alarm can achieve the function of the fire monitoring and alarm of large buildings. Microcontroller using STC89C52 as control device, with neat 8-bit CPU , which can provide many embedded control applications with high flexible and effective solution. MQ-2 type semiconductor gas sensitive element smoke sensor was used to detect smoke .When the sensor was in the environment with smoke gas, the conductivity of the transducer increased with the increased concentration of the smoke gas in the air. DSl8B20 temperature sensor detected temperature, compared with the conventional thermistor, which can read out the tested temperature directly and take simple programming to realize the 9 ~ l2 a digital direct reading method according to the requirements. The system with low design cost, high reliability, simple circuit design, can be widely used in all buildings fire monitoring.

Keywords:the fire alarm,MCU,sensor

目录

1  绪论 5

1.1  课题背景 5

1.2  设计概述 5

1.3  烟雾报警器的国内外现状 6

1.4  火灾报警器的发展趋势 6

2  总体方案设计 6

2.1  MQ-2半导体气体烟雾传感器 7

2.2  单片机选型 9

2.3  温度采集模块 11

3  系统的硬件电路 12

3.1  单片机最小系统 12

3.2  单片机的时钟电路与复位电路设计 13

3.3  烟雾检测AD采集电路 13

3.4  显示模块 14

3.5  声音报警电路 14

3.6  按键控制电路 15

3.7  电源模块 16

3.8  温度传感器(DS18B20)电路 17

4  系统软件的设计 21

4.1  系统主程序设计及流程图 21

5  硬件调试 23

结论 27

参考文献 28

致谢： 29

附录： 30

1 绪论

1.1  课题背景