数字示波器毕业设计

数字示波器毕业设计

篇一：基于单片机的数字示波器设计

摘要

示波器是电子测量中一种最常用的仪器，被广泛应用于各个领域。随着微电子技术和计算机技术的飞速发展，示波器也从模拟示波器向数字示波器发展。同模拟示波器相比，数字示波器具有很多优点，并开始逐步取代模拟示波器，成为市场上的主流。

本文主要完成了简易数字示波器的设计，包括硬件设计和软件设计两大部分。硬件设计上，信号波形采集采用的是12位逐次逼近型A/D转换器AD574A，转换时间为时间为25US，转换精度小于等于0.05%。控制器选用AT89C52及AT89C51两个单片机，解决了一般示波器使用一片单片机，运行速度明显不足的问题。波形显示部分采用液晶显示模块，具有简单易实现、显示效果好等优点。频率显示部分采用的是6位数码管显示，简单易行。

Proteus仿真表明，该设计运算速度明显提高。频率显示准确，可以实现快速读取。该示波器可以实现对模拟带宽为0.1KHz～20KHz的模拟信号的波形好频率的实时显示。

关键词：单片机；实时采样；波形；频率

Abstract

An oscilloscope is electronic measurement instrument, the most commonly used widely applied in various fields. With microelectronics and computer technology rapid development from analogue oscilloscope, oscilloscope to digital oscilloscopes development. Compared with analogue oscilloscope,digital oscilloscopes start has many advantages, and gradually replacing analogue oscilloscope, become the mainstream in the market.

This paper has completed the design of simple digital oscilloscopes, including hardware design and software design. The hardware design, the signal waveform sampling by 12 successive approximation of the A/D converter AD574A conversion time, for time is less than or equal to 25US conversion, precision 0.05%. Controller chooses AT89C52 and single-chip microcomputer, solve the two AT89C51 single-chip microcomputer, a commonly used oscilloscope shortage problem running speed. Waveform display part adopts LCD module is simple and easy to realize and shows good effect, etc. Frequency display part adopts is six

digital display, simple tube.

Proteus simulation shows that the design speed increased significantly. Frequency display correctly, can achieve rapid read. This can make the oscilloscope bandwidth for 0.1~20KHz to simulate the analog signal waveform 20KHz frequency of good real-time display.

Keywords:SCM ; Real-time sampling； waveform；frequency

目录

前言 ................................................ . (1)

1 数字示波器 (3)

1.1 数字示波器 (3)

1.2 本设计所要实现的目标 (4)

1.3 设计内容 (4)

2 系统设计 ................................................ (5)

3 数字示波器的硬件设计与实现 (6)

3.1 频率测量及显示电路的硬件设计 (6)

3.1.1 测频电路总体构成 (6)

3.1.2 信号调理电路设计 (6)

3.1.3 数码管显示模块 (9)

3.1.4 数码管显示驱动模块 (10)

3.2 幅度测量及显示模块的硬件设计 (11)

3.2.1 显示电路总体结构 (20)

3.2.2 单片机外围电路设计 (22)

3.2.3 信号波形采集模块 (24)

3.2.4 显示模块 (27)

3.2.5 电源设计 (30)

4 系统软件设计 (31)

4.1 测频系统软件设计 (31)

4.2 信号采集系统软件图 (33)

4.3 波形显示系统软件设计 (34)

5 调试及仿真 ................................................

36

6 结论 ................................................ (38)

致