基于单片机的波形发生器设计.doc

基于单片机的波形发生器设计 摘 要 波形发生器是一种常用的信号源，广泛地应用于科学研究、生产实践和教学实验等领域。特别是在通信系统的研究中，常常需要用到不同频率和相位的信号如三角波、锯齿波、方波、正弦波的电路等，因此多功能信号发生器应用十分广泛。目前使用的信号发生器大部分是函数信号发生器，且特殊波形发生器的价格昂贵。所以本设计使用的是DAC0832芯片构成的发生器，可产生三角波、方波、正弦波等多种特殊波形和任意波形，波形的频率可用程序控制改变，在单片机上加外围通过键盘控制波形的选择。在单片机的输出端口接DAC0832进行D/A转换，再通过运放进行波形调整，最后输出波形接在示波器上显示。 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，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。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、The Waveform Generator Design ABSTRACT Waveform generator is a kind of common source, widely used in scientific research, the production practice and teaching experiment, etc. Especially in the communication system of study, often need to use different frequency and phase signals such as triangle wave, the sawtooth wave, square wave, sine wave circuits etc, therefore multi-function signal generator used widely. Current use of signal generator is most function signal generator, and special waveform generator price expensive. So this design is using DAC0832 chip consists of the generator, can produce triangle wave, square wave, sine wave and so on many kinds of special waveform and arbitrary waveform, the frequency of the waveform can change control procedures, the microcontroller and peripheral keyboard control through the choice of the waveform. In the output port by single chip microcomputer DAC0832 on D/A transformation, again through the op-amp are waveform adjustment, finally the output waveform taken up in oscilloscope display. This paper introduce is to use AT89C51 single-chip microcomputer and analog-to-digital conversion device DAC0832 produce different low frequency signal source for signal, the signal amplitude and frequency can be according to the requirements of control. The paper briefly introduces the DAC0832 digital-to-analog converters structure principle and method of use, the basic theory of AT89C51, as well as wit