摘要
在科学研究中，示波器系统可获得大量的动态信息，是研究瞬间物理过程的有力工具。随着计算机技术的飞速发展和普及，数字示波器技术逐渐取代了模拟示波器技术。在数字示波器技术中，常用的采样方法有两种：实时采样和等效采样。实时采样通常是等时间间隔的，它的最高采样频率是奈奎斯特极限频率。等效采样是指对多个信号周期连续样来复现一个信号波形。本设计采用实时采样的方法，实现单片机简易示波器，在试验测试和工程制作中具有广泛的用途和应用前景。本单片机简易示波器的设计，在学习了单片机原理及其编程方法，单片机应用及接口技术，ADC0809 芯片的应用和图形点阵液晶显示模块 TG12864E 的使用方法后，基于单 片机系统的精密时钟发生电路对低频信号进行实时采样的方法，设计并实现一个模拟带宽为 400Hz～500Hz 的简易数字示波器。应用输入信号幅值为 0～5V，含 8 路选通开关的A/D 器件 0809 进行数据采集转换，应用 89C51 单片机控制输入输出和数据处理，128×64 全点阵液晶显示模块 TG12864E 显示输入信号波形。实验表明本设计电路结构简单，单片机控制频率、幅度步进，输入幅度 0～7.6V，能良好的在液晶显示模块上显示幅度 0～5V,频率 400Hz～500Hz 左右的输入信号波形，波形显示可以自动刷新，也可手动刷新，本系统可用于工程制作，具有一定的实用意义。
关键词：实时采样；单片机控制；数字示波器
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Abstract
In the Scientific research, oscillograph system can get A large amount of dynamic information, it is also a useful tool for a moment physical process. With the development at full speed and popularizing of the technology of the computer, the digitaloscilloscope technology has substituted for the simulation oscilloscope technology gradually. In the digital oscilloscope technology, there are two kinds of method for sampling , Real-timesampling and equivalent sampling. The real-time sampling is on usually the same time-gap, its highest sampling frequency is the Nyquist frequency. The equivalent sampling is As to the many signal period continual type reappears a waveform. This design uses the method of the real-time sampling, realizes Mirocontroller simple oscilloscope, it have the widespread use and the application prospect in the experimental test and the project manufacture. Before I design this Mirocontroller simple oscilloscope, I have studied the monolithic integrated circuit principle and programming method, Mirocontroller application and the connection technology, the ADC0809 chip application and the graph lattice liquid crystal display module TG12864E application method. This Mirocontroller simple oscilloscope has the electriccircuit based on Mirocontroller system precision clock to carry on the real-time sampling to the
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low-frequency signal the method, designs and realizes a simple digital oscilloscope which simulation band width is between the 400Hz ~ 500Hz. Using the input signal peak-to-peak value is 0 ~ 5V, it contains 8 groups to elect to pass the switch A/ D component 0809 carries on the data acquisition transformation, I use 89C51 Mirocontroller to control input output and data processing, 128 ×64 entire lattices liquid crystal display module TG12864E demonstration input signal profile. The experiment Indicate the electric circuit which I design is a simple structure, Mirocontroller control frequency, the scope step-by-step, input scope 0 ~ 7.6V, it can be good demonstrates scope 0 ~ 5V in the liquid crystal display module, about frequency 400Hz ~ 500Hz input signal profile, The profile demonstrated may automatically renovate, also may manual renovate, this system may use in the project manufacture, it has the certain practical significance.
Key words: Times Sampling; Mirocontroller;Oscillograph system
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目 录
第一章 前言 ........................................... 1 1.1选题的背景意义和研究现状 ......................... 1 1.1.1选题的背景和意义 ............ 错误！未定义书签。 1.1.2国内外研究现状 .............. 错误！未定义书签。 1.2设计的任务和要求................................. 4 1.2.1设计的基本要求 .............................. 4 1.2.2课题的具体工作内容 .......................... 4 1.2.3论文的结构安排 .............................. 7 第二章 数字示波器的基本原理 ............................ 8 2.1数字存储示波器的基本原理 ......................... 8 2.2系统的方案设计 ................................. 16 2.2.1系统的控制 ................................ 17 2.2.2输入模拟信号的处理 ......................... 18 2.2.3数字信号的采集与存储 ....................... 18 第三章 系统硬件电路的设计 ............................. 19 3.1单片机及其外围电路 .............................. 19 3.2信号输入电路单元................................ 22 3.2.1输入调理电路设计 ........................... 22 3.3 A/D转换电路 ................................... 23 3.3.1ADC芯片的选取 .............................. 23 3.3.2AD转换电路的硬件设计 ....................... 28
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3.4按键控制电路 ................................... 30 3.5液晶显示接口电路................................ 31 第四章 系统功能的软件设计 ............................. 33 4.1单片机软件开发系统 .............................. 33 4.2主程序设计及流程图 .............................. 34 4.3频率及幅值计算子程序设计 ........................ 35 4.3.1频率计算的原理及程序流程图.................. 35 4.3.2幅值计算的原理及程序流程图.................. 36 4.4显示子程序 ..................................... 37 第五章 存储示波器的制作与调试 ......................... 39 5.1调试和测试所用的仪器 ............................ 39 5.2样机的制作与调试................................ 39 5.2.1调试 ...................................... 39 5.3测试与结果分析 ................................. 42 5.3.1测试方案及方法 ............................. 42 第六章 结论和展望 ..................................... 43 6.1结论 ........................................... 43 6.2展望 ........................................... 43 致 谢 ............................................... 45 参考文献 .............................................. 1 附 录 ................................................ 2 1程序 .............................................. 2
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