电子秤毕业设计
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。
本设计以AT89S52单片机为主控芯片, 实现电子秤的基本控制功能。在设计系统时, 为了更好地采用模块化设计法, 分步的设计各个单元功能模块, 系统的硬件部分能够分为最小系统、数据采集和人机交互界面三大部分。最小系统部分主要包括AT89S52以及复位电路和晶振电路; 数据采集部分由稳重传感器、信号的前级处理和A/D转换部分组成, 包括仪表放大器INA122和A/D转换器ADC0804; 人机交互界面为键盘输入、点阵式液晶显示和语音报价, 主要使用4*4矩阵键盘、1602液晶显示模块和电子秤专用语音芯片SC1010B; 软件部分应用单片机C语言进行编程, 实现了该设计的全部控制功能。该电子秤能够实现基本的称重功能,能够设置单价, 还具有累加和报价功能。整个系统结构简单, 使用方便, 功能齐全, 具有一定的开发价值。
关键词: AT89S52, 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.
This design as the controller chip AT89S52 SCM, realize the basic electronic scale control function. In the design of the system, in order to better the modular design method, the design of the step each unit function module, the system's hardware parts can be divided into the smallest system, data acquisition and man-machine interface of three.Minimum system mainly including part and reset circuit AT89S52 crystal vibration circuit; Data acquisition in part by the steady sensors, signal processing and level before A/D conversion parts, including instrumentation amplifier INA122 and A/D converter ADC0804; The man-machine interface for keyboard input,Dot-matrix LCD display and voice offer, the main use 4*4 matrix
keyboard, 1602 LCD module and electronic scales special voice chip SC1010B; Application software of single chip microcomputer C programming language, realize the design of all control function. The electronic scales can realize the basic weighing function, can set the price,Also has the accumulation and offer function. The whole system structure is simple, easy to use, the function is all ready, has some of the development value.
KEYWORDS:AT89S52, ponderation –sensor, A / D converter, LCDDisplay
目录
摘要........................................................................................................................................... I ABSTRACT .............................................................................................................................. II 1 绪论. (1)
1.1 称重技术和衡器的发展 (1)
1.2 电子秤的组成 (1)
1.2.1 电子秤的基本结构 (1)
1.2.2 电子秤的工作原理 (2)
1.2.3 电子秤的计量性能 (3)
1.3 设计思路 (3)
2 系统方案论证与选型 (5)
2.1 测量部分 (5)
2.2 放大部分 (6)
2.3 A/D转换部分 (8)
2.4 控制器部分 (10)
2.5 显示部分 (10)
2.6 键盘部分 (14)
2.7 语音部分 (16)
3 硬件电路设计 (17)
3.1 AT89S52的最小系统电路 (17)
3.1.1、单片机芯片AT89S52介绍： (17)
3.1.2、单片机管脚说明： (18)
3.1.3、AT89S52的最小系统电路构成： (20)
3.2数据采集电路 (21)
3.2.1测量电路及放大电路 (21)
3.2.2 A/D转换电路 (22)
3.3显示电路 (24)
3.4语音电路 (26)
4 系统软件设计 (28)
4.1主程序流程图 (29)