发布时间 : 星期一 文章基于AVR单片机的便携式醉酒驾驶仪器设计 - 包含原理图和完整代码更新完毕开始阅读5a5fe11fc281e53a5802ff14
基于AVR单片机的酒精传感器的设计
——包含原理图和完整代码
摘要
该设计作品基于ATmega16单片机，利用酒精传感器，实现空气周围环境中的酒精浓度实时测量，通过LED数码管实时显示，一旦超过阈值即蜂鸣器报警，可用于车载监控及仓库等有防火要求的地方。
关键字
ATmega16单片机 酒精传感器 自动报警
Abstract
The design works based on single-chip microcomputer, using alcohol ATmega16 sensor, realize the alcohol concentration of air environment through real-time measuring, LED digital display, once more real-time tube threshold, which can be used for car buzzer alarm monitor and warehouse fire.
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目录
1 项目要求 ····························································································································· 4 2.项目的硬件原理和内容 ······································································································ 4 2.1 硬件设计思想和原理图································································································ 4 2.2 如何使用硬件单元········································································································· 4 2.3 硬件电路图····················································································································· 6 3.软件设计思想和内容 ·········································································································· 8 3.1端口初始化 ··················································································································· 8 3.2数据采集及处理流程······································································································ 8 3.3 LED显示 ························································································································· 9 3.4蜂鸣器报警······················································································································ 10 4.测试过程处理························································································································ 11 4.1硬件调试························································································································· 11 4.2仿真调试·························································································································· 11 4.3综合调试·························································································································· 12 4.4测试过程问题分析·········································································································· 13 4.5测试结论·························································································································· 14 5. 系统设计所需资源·············································································································· 14 6. 项目分工······························································································································ 14 7. 系统设计总结······················································································································ 14 7.1团队总结·························································································································· 14 7.2个人心得·························································································································· 15 参考文献 ······························································································································· 18 附录A 酒精传感器参数 ········································································································ 18 附录B 系统总程序代码 ········································································································ 20 附录C 实物图 ························································································································ 23
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一、 项目要求：
便携式酒后驾车测试仪
酒后驾车易出事故，但判定驾驶员是否喝酒过量带有较大的主观因素。请你利用学过的知识，设计一台便携式、交通警使用的酒后驾车测试仪。
总体思路是: 让被怀疑酒后驾车的驾驶员对准探头(内部装有多种传感器)呼三口气，用一排发光二极管指示呼气量的大小(呼气量越大，点亮的LED越多)。当呼气量达到允许值之后，“呼气气确认”LED亮，精酒蒸气含量数码管指示出三次呼气的酒精蒸气含量的平均百分比。如果呼气量不够，则提示重新呼气，当酒精含量超标时，LED闪亮，蜂鸣器发出“嘀??嘀??”声。
二、 项目的硬件设计原理与内容
1、 硬件设计思想和原理图：
采用MQ303将酒精信号转换成敏感体电阻的变化，外接电源和负载电阻，把电阻变化转换成电压信号，利用Mega16单片机的模数转换功能采样电压变化，转换成酒精浓度用七段数码管显示出来，当达到预定报警浓度时，蜂鸣器报警，并接通开关时，Led灯不再显示。
硬件设计时，考虑酒精浓度是由传感器把非电量转换为电量，传感器输出的是0-5伏的电压值且电压值稳定，外部干扰小等。因此，可以直接把传感器输出电压值送入单片机进行处理。此外，还需接入LED数码管显示，声光报警电路等。其总体框图右图所示： 2、 如何使用硬件单元：
将MQ303预留引脚接电源，预热3秒以上。接通单片机电源，七段数码管闪烁显示周围酒精浓度。一旦酒精浓度超过阈值，蜂鸣器报警。与门和非门以及开关组成打火系统，蜂鸣器信号和开关决定是否导通。开关模拟打火系统电源开关，接通开关时，Led灯亮表示打火成功，反之则表示打火系统被强行制止。
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单片机选择：ATmega16单片机是一款功能十分强大，集成度非常高的数字处理
系统。它集成了ADC与DAC的模块，因而此作品设计中可以直接将MQ3型酒精气敏传感器的探测信号输入单片机中，然后在单片机内进行A/D模数转换，数据处理。其引脚图如下图:
下图1为选择4位一体共阳极数码管，型号为SR410561k。该数码管具有工作
稳定，亮度高，反应灵敏，质量可靠等特点。
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