摘要：波形发生器是现代电子科研领域的重要信号源之一，其所产生的正弦波、方波、三角波和锯齿波等是较为常见的信号。科研人员以及电子类教学工作者常常会需要使用波形发生器进行信号仿真实验。随着科技的发展，电子信号频率上限、调制带宽和信号带宽不断拓展，高性能的波形发生器的技术实现也需要提高。

本文利用AT89C52单片机和数模转换器件DAC0832设计了一个低频的波形发生器，该波形发生器运用了数字波形合成技术。本次课题同时进行硬件的电路设计和软件的程序编写，最终可以输出方波、三角波和正弦波等三种波形。按键控制波形的种类并可以在一定范围内调节波形的频率，使用电位器可以在设定的范围内变换波形的幅度。处理器接收到按键和电位器的指令，便运行程序，发送数字信号给数模转换器。数模转换器随后输出模拟信号，经由放大电路放大，最后在示波器上输出波形。而LCD1602液晶显示屏显示波形的种类、幅值和频率。该波形发生器使用Proteus进行仿真，通过KeilC51编译程序。

关键词：AT89C52；波形发生技术；DAC0832

Abstract：Waveform generator is one of the important signal sources in the field of modern electronic research. The sine wave, square wave, triangular wave and sawtooth wave are the most common signals. Researchers and electronics instructors often need to use a waveform generator for signal simulation experiments. With the development of science and technology, the upper limit of electronic signal frequency, modulation bandwidth and signal bandwidth continue to expand, the higher performance waveform generator technology also need to improve.

In this paper, the use of AT89C52 microcontroller and digital-analog converter DAC0832 design of a low-frequency waveform generator, the waveform generator using digital waveform synthesis technology. The subject of the hardware circuit design and software programming, and ultimately can output square wave, triangular wave and sine wave and other three waveforms. The key controls the type of waveform and can adjust the frequency of the waveform within a certain range. The potentiometer can change the amplitude of the waveform within the set range. The processor receives the instructions of the key and the potentiometer, then runs the program, sends the digital signal to the digital- to-analog converter. The digital-to-analog converter then outputs the analog signal, amplifies it through the amplifier circuit, and finally outputs the waveform on the oscilloscope. The LCD1602 LCD display shows the type of waveform, amplitude and frequency. The waveform generator using Proteus simulation, through Keil C51 compiler.

Keywords: AT89C52; waveform generation technology;DAC0832

目录

第一章绪论-1

1.1研究背景1

1.2国内外波形发生技术的研究现状-2

1.3本文的主要内容2

第二章波形发生器的设计42.1引言4

2.2发生器各部分设计思路4

2.2.1信号发生部分4

2.2.2显示部分5

2.2.3键盘部分5

2.3本章小结7

第三章波形发生器的硬件实现-8

3.1电路硬件总体设计8

3.1.1AT89C52单片机介绍9

3.1.2DAC0832的介绍-11

3.1.3LM358N运放电路介绍12

3.1.4键盘译码器MM74C922介绍12

3.2电路各部分硬件实现-13

3.2.1显示接口电路-13

3.2.2波形转换电路14

3.2.3复位电路-15

3.2.4外部时钟电路-15

3.3本章小结-16

第四章波形发生器的软件实现17

4.1电路软件总体设计-17

4.2波形发生器的各子程序-18

4.2.1键位扫描子程序设计-18

4.2.2波形数据产生子程序-19

4.2.3正弦波程序设计-20