煤气报警器设计.doc

煤气警报器设计

摘  要

当今社会上，出现了许多煤气报警器，而这些产品大都是针对煤气的泄漏所做出的相应的报警，即为家庭式煤气报警器。本课题设计煤气报警采用了AT89S52单片机为报警器的核心部件，对煤气报警器进行控制。通过NAP-505电化学一氧化碳气体传感器对煤气进行检测，将所得的浓度值与设定浓度值相比较得到偏差。通过对偏差信号的处理获得控制信号，发生报警信号，并把报警通道显示并储存在DS12887的RAM中，八个单元的煤气浓度对应模拟量利用A/D转换为数字量，并加入了键盘输入控制，从而实现对家用和工业煤气漏气的监控。整个系统的硬件电路设计合理，性能安全可靠。

关键词：单片机 煤气浓度 报警器
 

Design of the coal gas’ alarm device

ABSTRACT

There are many coal gas alarm’s devices in our lives. These devices will alarm after the coal gas leaking. We call them household or industy appliances. This paper introduces the design of a coal gas alarm’s device that use the AT89S52 SCM as the most important controller. It is a core-components that control the whole programs and circuit of the coal gas alarm’ device. The appliance monitors the density of coal gas with the sensor of NAP-505 and compares the current density with the setting density. We get the control signal through the dealing with the deviation signal and then sent a alarm signal that is memoried in a RAM of DS12887. The analog signal of eight densities of the coal gas are transformed into the digital signal with the A/D converter, in addition which is cotrolled with the keyboard. We can monitor the leak of coal gas in the house or industy. The hardware design of circuits is reasonable and the performance of the coal gas alarm’s device is safe and reliable.
   
Keywords: SCM  Density  Alarm’ device

目  录
摘  要 I
ABSTRACT II
1  前言 1
1.1研究背景 1
1.2研究意义 2
1.3研究内容 2
2  系统总体设计 3
2.1方案的选择 3
2.2系统流程框图 3
3  硬件系统设计与传感器选用 4
3.1主机部分 4
3.1.1AT89S52单片机 4
3.1.2DS12887实时时钟芯片及其电路 6
3.1.3X5045看门狗定时器及复位电路 8
3.1.4 电源电路 9
3.2功能模块部分 9
3.2.1TLC2543的数据采集单元 10
3.2.2HD7279的人机接口电路模块 12
3.2.3数据处理模块 15
3.2.4声光报警模块 16
3.2.5ISP下载电路DIY 17
3.3传感器的选用 18
3.3.1NAP-505型电化学式传感器 19
3.3.2MQ-9半导体气体传感器 20
3.4硬件设计小结 22
4  软件设计 23
4.1主程序设计 23
4.1.1初始化程序和主程序 23
4.1.2中断服务程序 27
4.2功能实现主要子程序 28
4.2.1采集程序 28
4.2.2数据处理模块 30
4.2.3报警记录和报警模块 31
4.2.4人机对话子程序设计 31
4.3小结 34
5  系统调试与分析 35
5.1硬件焊接与调试 35
5.2软件调试 36
5.3系统调试 38
5.4小结 39
参考文献 40
附  录1 程序源代码 41
附  录2 焊接实物图 56
附  录3 元器件清单 58
谢  辞 60