摘要近几十年来，单片机发展十分迅速，当前单片机广泛地应用于小系统内，涵盖了众多的对象系统（如家用电器、仪器仪表、控制单元等），极大地便利了人们的生活和工业上的控制。而且，低、中档单片机无论从价位、功能和体积方面都远优于用大量的数字集成电路硬件组合而成的系统,几乎可以在任何用电的产品中使用，其市场潜力巨大，总是不断地超出人们的预料。仪器仪表的设计是单片机应用的一个重要方向，基于单片机的数字仪表极大集成诸多功能于一体，具有检测准确、故障率低、结构紧凑等优点。
本课题的数字多用表是基于80C51单片机设计的，主体思路为首先通过测量电路测得需要的值，由于ADC0808转换的需要，测量的参数需要转化为电压值，接着ADC0808将测得的值进行A/D转换并传输给单片机，单片机由程序控制对该测量值进行数据处理，最后在通过LCD显示。9917
本课题设计的多用表具有用途广，测量精确，使用方便的优点，可用来精确测量电压，电流，电阻。
关键词 单片机 数字多用表 A/D转换 LCD显示
毕业设计说明书（论文）外文摘要
Title The Design of Digital Multimeter Based on 51 SCM
Abstract
In recent decades, SCM has developed very rapidly. Now, SCM is widely used in small systems, covering many object systems (such as domestic appliance, instruments and meters, control unit, etc.), which brings great convenient for people's life and industrial control. Furthermore, low and middle-grade SCMs are far superior to those systems made by a large amount of digital integrated circuits, whether to the price, function or volume. SCM can almost be used in every electronic production, so it gains a tremendous market potential, which is beyond what people had expected. The design of meter is an important direction of SCM application. Digital meters based on SCM greatly integrate many functions with the merits as accurate testing, low failure rate and compact structure.
In this design, the digital meter is based on 80C51 SCM. First we get the value we need by measuring circuit. Because of the limit of ADC0808, we need to convert the value into a voltage value. The ADC0808 will convert it into a digital number and transmit the number to SCM. Through the data processing, we can gain the result and display it in LCD.
The digital meter in this design can be used to accurately measure voltage, current and resistance.
Keywords SCM DMM A/D conversion LCD display
目 次
1 引言 1
1.1 数字多用表的发展现状 1
1.2 本课题的任务 1
2 数字多用表方案设计 2
2.1 数字多用表工作原理 2
2.2 数字多用表硬件电路设计 2
2.3 仿真软件Proteus简介 16
3 数字多用表软件设计 17
3.1 键盘选择模块 18
3.2 A/D转换模块 19
3.3 电阻测量数据处理模块 19
3.4 电压测量数据处理模块 20
3.5 电流测量数据处理模块 21
3.6 LCD显示模块 22
4 结果分析 24
4.1 电阻测量结果分析 24
4.2 电压测量结果分析 25
4.3 电流测量结果分析 26
5 结束语 28
结 论 29
致 谢 30
参 考 文 献 31
1 引言
1.1 数字多用表的发展现状 基于51单片机数字多用表的设计:http://www.751com.cn/zidonghua/lunwen_8803.html