基于单片机的波形发生器课程设计版

基于单片机的波形发生器

摘要

本系统是基于AT89C51单片机的数字式低频信号发生器。采用A T89C51单片机作为控制核心，外围采用数字/模拟转换电路（DAC083 2）、运放电路（LM324）、按键和8位数码管等。通过按键控制可产生方波、三角波、正弦波等，同时用数码管指示其对应的频率。其设计简单、性能优好，可用于多种需要低频信号的场所，具有一定的实用性。

各种各样的信号是通信领域的重要组成部分，其中正弦波、三角波和方波等是较为常见的信号。在科学研究及教学实验中常常需要这几种信号的发生装置。为了实验、研究方便，研制一种灵活适用、功能齐全、使用方便的信号源是十分必要的。

本文介绍的是利用AT89C51单片机和数模转换器件DAC0832产生所需不同信号的低频信号源，其信号幅度和频率都是可以按要求控制的。文中简要介绍了DAC0832数模转换器的结构原理和使用方法，AT89C51的基础理论，以及与设计电路有关的各种芯片。文中着重介绍了如何利用单片机控制D/A转换器产生上述信号的硬件电路和软件编程。信号频率幅度也按要求可调。

本次关于产生不同低频信号的信号源的设计方案，不仅在理论和实践上都能满足实验的要求，而且具有很强的可行性。该信号源的特点是：体积小、价格低廉、性能稳定、实现方便、功能齐全。

关键词：AT89C51DAC0832 LM324 8位数码管显示

Abstract

Waveform The system is a digital signal generator based on single chip computer.At89c51 is used as a control microcontroller core.The system is composed by digital/analog comversion(DAC0832), imply circuit,button and nixie tube.It can generate the square, triangle and sine wave,with nixie tube.The system can be used for a signal soure in the low-frequency signal soure.It is very practical.

Various signals are an important part of correspondent area. In this area, sine wave, triangle wave and square wave are common signals. In science research and teaching experiment, we often need the occurrence equipment of these signals. In order to make the experiment and research easier, to develop a suitable, full functional and easily used signals source is essential.

This paper introduces the low frequency sources of different signals that are produced by AT89C51 SCM and DAC0832. Its signal range and frequency can be controlled by requirement. This paper briefly introduces the structure principle and usage of DAC0832, the basic theory of AT89C51 and various chips which relevant to design circuit. this paper emphasized how to use SCM to control the hardware circuit and software program of the signals above which produced by DAC0832. The signal frequency range also can be adjusted by requirement.

This signal source design plan concerns on producing different low frequency signals, not only meet the request of experiment in theory and in practice, but also have strong feasibility. The trait of this signal source is: small volume, low price, stable function, easily achievable, and full function. Keywords:AT89C51, DA0832, LM324, 8 nixie tube display

目录

摘要............................................................................................................ I Abstract.................................................................................................. II 目录......................................................................................................... III 前言.. (1)

1 波形发生器概述 (2)

1.1波形发生器的发展状况 (2)

1.2国内外波形发生器产品比较 (4)

2 方案论证与比较 (5)

2.1 方案一 (5)

2.2 方案二 (6)

2.3 方案三 (6)

3 硬件原理 (8)

3.1 MCS-51单片机的内部结构 (8)

3.1.1 内部结构概述 (8)

3.1.2 CPU结构 (9)

3.1.3 存储器和特殊功能寄存器 (10)

3.2 P0-P3口结构 (11)

3.3 时钟电路和复位电路 (11)

3.3.1时钟电路 (11)

3.3.2单片机的复位状态 (12)

3.4 DAC0832的引脚及功能 (13)

4 软件原理 (15)

4.1 主流程图 (15)

4.2 锯齿波仿真图 (16)

4.3 三角波仿真图 (17)