摘要该设计主要内容是制作出一款具有输入、显示、参数变更等功能的波形发生器。其核心部分为单片机（此次制作选用AT89C51芯片），通过键盘输入指令信号，然后交由单片机处理并发出，交由D/A（模数）芯片转变成模拟信号，接着经由运算放大芯片（LM358）的处理，并最终将计算结果显示在液晶屏幕上。

为了使文章内容全面，本文还重点介绍了89C51的端口功能及常用方法；还有模数转换和运放电路的功能特性以及相关电路设计方面的芯片介绍，与此同时，还着重说明了利用单片机控制数模转换器产生以上信号的软件编程与硬件电路设计。49200

总的来说，此系统构造简单易懂，仿真结果上的表现也令人满意，且如果做实物所需材料也非常有限，可以节省很多费用，具有相当不错的性价比。

该论文有图24幅，表4个，参考文献25篇。

毕业论文关键词：单片机  D/A转换  信号发生器  运算放大器

 Design and Realization of multi function signal generator based on 51 single chip microcomputer

Abstract 

This paper mainly designs a signal generator which has the function of input, display and parameter change. The main single-chip microcomputer for core (the design use AT89C51 models), through the keyboard input command signal, by SCM processing and output, by D / a (ADC) into analog signal, again through the lm358 op amp, and, ultimately,And finally the calculation results are displayed on the LCD screen.

In order to make the content of the article is comprehensive. This article focuses on the 89C51 port function and commonly used method; and the functional properties of the analog to digital conversion and operational amplifier circuit and the design of circuit chip is introduced. At the same time, the article also describes the use MCU to control digital to analog conversion, software programming and hardware circuit design of those signals is produced.

In general, this system has the advantages of simple structure and easy to understand, the simulation results of the performance is satisfactory, and if the kind of required materials are very limited, can save a lot of cost, has a good price.

 Keywords：singlechip  Digital to analog conversion  Signal generator  Operational amplifier

 目  录 

摘  要 I

Abstract II

图清单 IV

表清单 IV

1 概 述 1

2 系统设计 3

2.1 系统方案的选择 3

2.2 控制芯片的选择 3

3 系统硬件设计 4

3.1 基本原理 4

3.2 单片机介绍及资源分配 4

3.3 系统各模块电路原理 9

4  系统软件的设计 19

4.1  主程序的流程图 19

4.2 子程序流程图 20

5 测试结果 25

6 实物图部分展示 27

7 结论 28

致 谢 29

参考文献 30

附录A 元件清单 32

附录B 系统电路原理图、仿真图