基于51单片机的商业用智能电子秤设计

摘要

随着微电子技术的应用，市场上使用的传统称重工具已经满足不了人们的要求。为了改变传统称重工具在使用上存在的问题，在本设计中将智能化、自动化、人性化用在了电子秤重的控制系统中。本系统主要由单片机来控制，测量物体重量部分由称重传感器及A/D转换器组成，加上显示单元，此电子秤俱备了功能多、性能价格比高、功耗低、系统设计简单、使用方便直观、速度快、测量准确、自动化程度高等特点。

本系统以AT89C51单片机为主控芯片，外围附以称重电路、显示电路、键盘电路等构成智能称重系统电路板，从而实现自动称重系统的各种控制功能。可以说,此设计所完成的电子秤很大程度上满足了应用需求。

关键词AT89C51 称重传感器 A/D转换器 LCD显示器

Abstract

With the application of micro-electronics technology, tradition ponderation instrument used in market has been not satisfaction with hunman requirements already. In order to make up for the traditional apparatus shortcoming, we improve the apparatus's control system with intelligence and automation. This system is mainly controlled by microcontroller, the section of height measurement accomplish by supersonic sensor, the section of weight measurement accomplish by weight sensor and A/D transformer, this apparatus have many characteristic such as having more function, consume less energy, small and move easily, low price, measure precisely, the speed is quick, automatic work without people and so on.

The system is mainly controlled by the microcontroller AT89S52, the periphery is consist of the circuit of clock and calendar, the circuit of measure height and weight, the circuit of display and print, all of these comprise the circuit board of the intelligent apparatus of height and weight. It can achieve all function of the apparatus.

Key Words:AT89C51; weighing sensor; A / D converter; LCD Monitor

目录

摘要.......................................................................................................................................................................... I ABSTRACT..................................................................................................................................................................... II 第一章绪论.. (1)

1.1电子秤的概述 (1)

1.2设计目的 (2)

第二章系统方案的设计 (1)

2.1设计要求 (1)

2.2进度安排 (1)

2.3电子秤的工作原理 (1)

2.4系统的整体设计思路 (2)

第三章系统硬件电路设计 (5)

3.1压力传感器 (5)

3.2前级放大器 (8)

3.2.1反相比例运算电路 (8)

3.2.2前级放大电路 (10)

3.3A/D转换器 (11)

3.3.1方案比较 (11)

3.3.2ADC0832芯片介绍 (12)

3.3.3采样电路图 (12)

3.4控制器 (13)

3.4.1AT89C51芯片介绍 (14)

3.4.2单片机最小系统 (16)

3.5输入键盘 (17)

3.5.1矩阵键盘仿真及接线图 (18)

3.5.2矩阵键盘工作原理 (18)

3.6输出显示 (18)

3.6.1LCD12864介绍 (19)

3.6.2LCD显示电路图 (21)

3.6.3LCD的驱动 (21)

第四章系统软件的设计 (22)

4.1主程序设计 (22)

4.2A/D转换启动及数据读取程序设计 (23)

4.3键盘子程序 (24)

4.4显示子程序 (25)

第五章仿真调试 (26)

5.1 PROTEUS软件介绍 (26)

5.2仿真步骤 (27)

5.3调试故障及原因分析 (28)

结论 (29)

参考文献 (30)

致谢 ......................................................................................................................................... 错误！未定义书签。附录一硬件电路仿真图.. (31)

附录二程序清单 (32)