摘要:针对传统信号发生器存在元器件分散性造成波形失真的弊端,本系统提出了利用单片机AT89C51采用程序设计方法产生正弦波、方波、三角波三种波形,数字信号通过D/A转换器DAC0832转换成模拟信号,滤波放大,最终由示波器显示出来,能产生1Hz—3kHz的波形。通过键盘来控制三种波形的类型选择、频率变化,并通过液晶屏1602显示其各自的类型以及数值,系统主要包括信号发生、数/模转换以及液晶显示三部分,其中对数/模转换部分和波形产生和变化部分进行详细论述。56775
经验证,本设计性价比高,波形失真小,可靠性好,解决了波形失真的弊端。
毕业论文关键词:单片机AT89C51,DAC0832,液晶1602
Abstract: As for the defects of wavefoem distortion caused by the traditional waveform generator for the existence of scattered components,this system capitalize on AT89C51,it makes use of central processor to generate three kinds of waves, they are triangle wave, and use D/A conversion module, wave generate module and liquid crystal display of 1602, it can have the 1Hz-3KHz profile. In this system it can control wave form choosing, frequency, range,can have the sine wave, the square-wave, the triangular wave. Simultaneously may also take the frequency measurement frequency,and displays them through liquid crystal display of 1602. this design includes three modules. They are D/A conversion module, wave generate module and liquid crystal display of LED module. In this design, the wave generator into wave form module and D/A conversion module are discussed in detail.
After verification, the design of high performance price ratio, small waveform distortion, good reliability, solves the problem of waveform distortion.
Key words: AT89C51,DAC0832,liquid crystal 1602
目录
1 前言 4
1.1 选题背景及意义 4
1.2 信号发生器的分类 4
2 系统设计 5
2.1方案设计与论证 5
2.1.1 信号发生电路方案论证 5
2.1.2 单片机的选择论证 5
2.1.3 显示方案论证 6
2.1.4 键盘方案论证 6
2.2 总体系统设计 6
3 硬件设计及单元电路设计 7
3.1 单片机最小系统设计 7
3.2 波形产生模块设计 8
3.3 显示模块的设计 9
3.4 键盘模块设计 10
4 软件设计流程 11
4.1 正弦波产生流程 12
4.2 三角波产生流程 12
4.3 方波产生流程 14
5 输出波形的种类与频率的测试 15
5.1 测量仪器及测试说明 15
5.2 测试过程 15
5.3测试结果 17
结 论 18
参考文献 19
致 谢 20
附录一:总体原理设计图 21
附录二:源程序 22