毕业设计：基于AT89S51单片机的电子称设计.doc

摘要 称重技术自古以来就被人们所重视，作为一种计量手段，广泛应用于工农业、科研、交通、内外贸易等各个领域，与人民的生活紧密相连。目前，商用电子秤的使用非常普及，逐渐会取代传统的杆秤和机械案秤。电子秤是电子衡器中的一种，衡器是国家法定计量器具，是国计民生、国防建设、科学研究、内外贸易不可缺少的计量设备，衡器产品技术水平的高低，将直接影响各行各业的现代化水平和社会经济效益的提高。因此，称重技术的研究和衡器工业的发展各国都非常重视。 通过分析近年来电子衡器产品的发展情况及国内外市场的需求，电子衡器总的发展趋势是小型化、模块化、集成化、智能化；其技术性能趋向是速率高、准确度高、 稳定性高、可靠性高；其功能趋向是称重计量的控制信息和非控制信息并重的“智能化”功能；其应用性能趋向于综合性和组合性。 本文是基于AT89S51单片机的一种电子称重设备的设计说明。论文首先简要叙述了电子秤的主要背景以及总体的设计方式；然后详细阐述了数字电子秤的设计流程，以及硬件系统和软件系统的设计，并给出了硬件电路的设计细节。本系统主要分为四大部分，信号前级为称重传感器和放大滤波电路，电阻应变式称重传感器，利用全桥测量原理，将重力信号转换成电信号来测量。单片机为主要部件，完成数据处理和对各个部分的控制，通过对电路输出电压和标准重量的线性关系，建立具体的数学模型，将电压量纲（V）改为重量纲（g）。人机界面部分由六位LED管显示与4×4位矩阵键盘组成，可以由键盘控制显示重量和价钱等信息。 关键字：电子秤；称重传感器；AT89S51单片机；A/D转换器；LED数码管 Abstract Weighing technology from time immemorial attention, as a measurement method, widely used in industry, scientific research, transportation, and trade fields, and peoples lives are closely linked. At present, the use of electronic commercial very popular, and gradually will replace the traditional GanCheng and machinery. Electronic is a kind of electron weighing apparatus, instruments is the national legal measuring instruments, livelihood, national defense, science research, domestic and foreign trade indispensable measure equipment, instruments, product technical level will directly influence the from all walks of life and social modernization level economic benefit. Therefore,weighing technology research and development of all industrial instruments very seriously. Weighing in recent years through analysis of electronic products and the development of domestic and international market demand, electronic weighing the overall development trend is small and modular, integrated, intelligent; their technical performance trend rate is high, high accuracy, stability High, high reliability, its function is weighing measures tend to control information and non-control information both the intelligent functions of its application performance tend to be comprehensive and combinations of. This artic