毕业论文：基于单片机的电子闹钟设计（终稿）.doc

PAGE 38 摘 要 单片机自20世纪70年代问世以来，以其极高的性能价格比，受到人们的重视和关注，应用很广、发展很快。而51单片机是各单片机中最为典型和最有代表性的一种。 本文设计以AT89S51芯片为核心，辅以必要的外围电路，设计了一个结构简单，功能齐全的电子时钟，它由5V直流电源供电。在硬件方面，除了CPU外，使用六个七段LED数码管来进行显示，LED采用的是动态扫描显示，使用74LS14芯片进行驱动。通过LED能够比较准确显示时、分。两个简单的按键实现对时间的调整。软件方面采用汇编语言编程。整个电子钟系统能完成时间的显示、调时、定时闹钟和复位等功能。  选用单片机最小系统应用程序,添加比较程序、时间调整程序及蜂鸣程序，通过时间比较程序触发蜂鸣，实现闹钟功能，完成设计所需求的软件环境。介绍并使用Keil单片机模拟调试软件，测试程序的可行性。 关键词：单片机技术，AT89S51，液晶驱动，电子闹钟  ABSTRACT Because of its extremely high performance-price ratio, the single-chip computer (SCC) has been paid great attention to ever since it came out in 1970s of 20th Century, and has gained an extensive applicable field and fast development. Among all kinds of SCCs, 51 SCC is the most typical and representative one. This design, adopting AT89S51 chip as the core part with some necessary peripheral circuits, is a simple electronic clock which uses 5V DC as the power supply. In hardware aspect, besides the CPU, six seven-segment LED digi-tubes are used for display, which work in a dynamically scanning display mode and driven by 74SL14 chip. The LEDs can accurately indicate hour and minute and two buttons can be used to adjust the time. While in the software aspect, the programming language is assembly language. The whole electronic clock system has functions of time display, adjustment, bell-setting and reset, etc. Choose the smallest SCM system applications,add Comparison procedures, time to adjust procedures and faint buzzing procedures, Through relatively faint buzzing trigger procedures to achieve alarm clock function, Completed the design needs of the software environment. Keil introduced and the use of SCM software simulation debugging, testing the feasibility. Keywords: technology of the one-chip computer，AT89S51，the liquid crystal is driven，Electronic alarm clock   PAGE 8 目 录  TOC \o 1-3 \h \z \u  HYPERLINK \l _Toc171439899 第1章 绪 论  PAGEREF _Toc171439899 \h 1  HYPERLINK \l _Toc171439900 1.1 单片机简介  PAGEREF _Toc171439900 \h 1