大学毕设论文__基于单片机的时钟电路设计.doc

基于单片机的时钟电路设计 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，51单片机是各单片机中最为典型和最有代表性的一种。 本次设计以AT89C51芯片为核心，辅以必要的外围电路，设计了一个简易的电子时钟，它由5V直流电源供电。在硬件方面，除了CPU外，使用四个七段数码管来进行显示，数码管采用的是动态扫描显示。通过数码管能够比较准确显示时、分,LED一闪一灭显示秒，设计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、复位等功能。 通过这次设计让我更深入了解单片机基本电路、如何控制和定时器和中断编程的基本方法，从而锻炼了我学习、设计和开发软、硬件的能力。 关键词：AT89C51 ；单片机 ；数码管 ? ? ? ? ? ? ? Based on single-chip clock circuit design Abstract Because of its extremely high performance-price ratio, the single-chip computer has been paid great attention to ever since it came out in 1970s of 20th Century, and hagained extensive applicable field and fast development.Among all kinds of SCCs, 51 SCC representative one. This design, adopting AT89C51 chip as the core part with some necessary periphcircuits, is a simple electronic clock which uses 5V DC as the power supply. In hardware besides CPU, four seven-segment LED digi-tubes are used for display, which work in a dynamicallscdisplay mode and driven by 74SL14 chip.The LEDS can accurately indic ate hour and minute and assembly language.The whole electronic clock system has functions of time disadjustment, bell-setting and reset, etc. This design enables me to have greater insight into the basic circuit of SCC, and thbasic methods of timer control and interruption programming, so that is a training of my abilearning, designing and developing software and hardward. keywords: AT89C51; SCM ; Digital 目录 1 绪论....………………………………………………………………………..…...1 1.1 选题的目的和意义……………………………………………………………….…1 1.2 单片机的应用………………………………………………………………3 1.3 单片机数字时钟的总体设计方案…………………………………………3 2 硬件分析………………………………………………………………………….6 2.1 单片机的选用………………………………………………………………6 2.1.1 AT89C51的主要性能参数…………………………………………………..6 2.1.2 引脚说明……………………………………………………………...7 2.1.3 复位电路……………………………………………………………...8 2.2 数码管的选择………………………………………………………………8 2.2.1 数码管的主要特点…………………………………………………...8 2.2.2 驱动方式……………………………………………………………...9 2.2.3 性能检测……………………………………………………………...9 3 系统设计………………………………………………………………………