毕业论文（设计）
上传者：傅浩
傅浩 傅浩 傅浩 傅浩
基于单片机的数字频率计的设计
【摘要】
本设计以AT89S52单片机为核心充分利用硬件资源设计的一种频率计，该频率计首先将被测信号放大整形处理，变成满足单片机I/O口接受的TTL/ CMOS 兼容信号从单片机的T1输入口输入直接累加脉冲数，将单片机内部定时器定时为1S，这时累加的脉冲数即为被测信号的频率。最后经单片机处理送至lcd液晶显示屏显示。
【关键字】 单片机（AT89S52）、放大整形、 数据处理、1602aLCD、
【Abstract】
This design take at89S52 monolithic integrated circuit as the core full use hardware source design's one kind of frequency meter, this frequency meter will be measured first that signal enlargement reshaping processing, turns satisfies TTL/which the monolithic integrated circuit I/O mouth accepts the CMOS compatible signal from monolithic integrated circuit's T1 input port input direct summation pulse number, the monolithic integrated circuit interior timer fixed time is 1S, by now accumulated the pulse number namely for is measured the signal the frequency. Finally passes through monolithic integrated circuit processing to deliver to the lcd liquid crystal display monitor demonstration.
【Keyword】AT89S52、 Larger plastic、Data processing、1602aLCD
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目录
引
言??????????????????????????????
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1.系统概
述??????????????????????????????
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1.1数字频率计概
述????????????????????????????5
1.2频率测量仪的设计思路与频率的计
算 ????????????????????5
1.3基本设计原
理 ????????????????????????????5
2.数字频率计（低频）的硬件结构设
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计????????????????????5
2.1 系统硬件的构
成 ???????????????????????????5
2.2 AT89S52单片机及其引脚说
明 ??????????????????????6
2.3 信号调理及放大整形模
块 ????????????????????????7
2.3.1工作原理
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2.3.2 信号放大仿真
图 ?????????????????????????8
2.3.3 信号转换成方
波 ?????????????????????????8
2.3.4 LF353双运算放大器简
介 ?????????????????????8
2.4 显示模
块 ?????????????????????????????
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2.4.1 1602ALCD与单片机的接
法 ?????????????????????9
2.4.2 1602ALCD基本技术
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3.软件设
计 ?????????????????????????????
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3.1 系统工作流程
图 ???????????????????????????12
3.1.1 T0的1s定
时??????????????????????????13
3.1.2 T1的计数原
理 ?????????????????????????13
3.2 软件工作原
理 ????????????????????????????14
3.3 软件处理方
法 ????????????????????????????14
4.实验结果与分
析 ????????????????????????????15
4.1实验数
据 ?????????????????????????????
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4.2实验结果分
析 ????????????????????????????15
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