摘要：随着数字化的快速发展，电子称重技术得到较大的普及，各式各样的电子秤已经深入生活的各个方面。然而一些商用电子秤也出现了一些局限性，例如大型超市使用的电子秤由于体积庞大、精度不高、容易损坏等缺陷，对一些质量很小的物体称重存在较大的误差，从而需要更精确的测量仪器。本文设计了一种便携式电子秤，其以STC89C51单片机为主控芯片，该电子秤包括电源、LED数码管、称重传感器以及开关。本设计采用应变式压力传感器作为称重元件，采集数据，经过A/D转换后传送给单片机，单片机对数据进行处理，最后将输出结果显示在LED数码管上。该电子秤具有体积小、测量精度高、操作简单、成本低、易携带等特点，具有广阔的应用前景。78335

毕业论文关键字：压力检测，单片机，LED数码管

Abstract:With the rapid development of digital, the popularity of electronic weighing technology improved, all kinds of electronic scale has been deep into all aspects of life。 However some commercial electronic scale also have some limitations, such as large supermarket use electronic scale due to the huge volume, accuracy is not high, easy to damage, the quality of some weighing very small objects exist large error, which need to be more precise measuring instrument。 In this paper, we design a portable electronic scales, the STC89C51 microcontroller as the main control chip, the electronic scale including power, LED digital tube, the weighing sensors and switches。 This design USES the strain type pressure sensor as weighing device, data acquisition, the A/D conversion will be sent to SCM, single-chip computer for data processing,the final will be output in LED digital tube display。 The electronic scale has small volume, high measuring accuracy, simple operation, low cost and easy to carry, has a broad application prospect。

Keywords:Pressure measurement,Single chip microcomputer,LED

目录

1 绪论： 4

1。1 选题的目的和意义 4

1。2 电子秤的发展现状 4

1。3主要工作以及任务分析 5

2 系统方案分析与硬件选择 5

2。1 系统方案分析 5

2。2 传感器的选择 6

3 硬件设计及其各模块电路的设计 7

3。1单片机核心模块设计 7

3。1。1 复位电路 8

3。1。2 晶振电路 9

3。2外围电路系统设计 9

3。2。1蜂鸣器报警电路 9

3。2。2 LED数码管 10

3。2。3 LED灯接线图 10

3。2。4电源供电模块 11

3。2。5按键模块 11

3。2。6单片机模块 11

3。3电子秤组成部分详解 12

3。3。1 传感器工作原理 12

3。3。2 单片机基本原理及介绍 13

3。3。3显示器选择 15

3。3。4 DC电源插口 15

3。3。5 实物原理图 16

4 软件设计