毕业论文电子钟

毕业设计（论文）

院 校： 学院

专 业： 应用电子技术

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年 月 日

单片机电子钟

专 业：应用电子技术 班 级：

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摘 要

近年来随着计算机在社会领域的渗透和大规模集成电路的发展，单片机的应用正在不断地走向深入，由于它具有功能强，体积小，功耗低，价格便宜，工作可靠，使用方便等特点，因此特别适合于与控制有关的系统，越来越广泛地应用于自动控制，智能化仪器，仪表，数据采集，军工产品以及家用电器等各个领域，单片机往往是作为一个核心部件来使用，在根据具体硬件结构，以及针对具体应用对象特点的软件结合，以作完善。

本设计是定时闹钟的设计，由单片机AT89C51芯片和LED数码管为核心，辅以必要的电路，构成的一个单片机电子定时闹钟。电子钟设计可采用单片机来完成。数字电子钟是用数字集成电路构成的，用数码管显示“时”，“分”，“秒”的现代设计装置。若用数字电路完成，所设计的电路相当复杂，大概需要十几块数字集成块，其功能也主要依赖于数字电路的各功能模块的组合来实现，焊接的过程比较复杂，成本也非常高。若用单片机来设计制作完成，由于其功能的实现主要通过软件编程来完成，那么就降低了硬件电路的复杂性，而且其成本也有所降低，所以在该设计中采用单片机利用AT89C51，它是低功耗、高性能的CMOS型8位单片机。AT89C51单片机结合七段显示器设计的简易定时闹铃时钟，可以设置现在的时间及显示闹铃设置时间，若时间到则发出一阵声响，进一步可以扩充控制电器的启停。

设计容包括了秒信号发生器、时间显示电路、按键电路、供电电源以及闹铃指示电路等几部分的设计。采用四个开关来控制定时闹钟的工作状态，分别为：K1、设置时间和闹钟的小时：K2、设置小时以及设置闹钟的开关：K3、设置分钟和闹钟的分钟：K4、设置完成退出。

本次做的数字钟是以单片机（AT89C51）为核心，结合相关的元器件,再配以相应的软件，达到制作简易数字钟的目的，其硬件部分难点在于元器件的选择、布局及焊接。

关键字：单片机 AT89C51 共阳极LED数码管显示器

Abstract

In recent years, with computers in the infiltration and the

development of large-scale integrated circuits. SCM application

is steadily deepening, as it has strong function, small size, low

power dissipation, low prices, reliable, easy to use features, it

is particularly suited to and control of the system, increasingly

widely used in automatic control, intelligent instruments, gauges,

data acquisition, military products and household appliances, and

other areas, is often microcontroller as a core component to use,

In light of specific hardware architecture, and

application-specific software features object combine to make

perfect.

This design is the design of timing clock from the

microcontroller AT89C51 chip and LED digital tube as the core,

supplemented by the necessary circuitry, consisting of a

microcontroller electronic time clock. MCU clock design can be used

to complete. Digital electronic clock is composed of digital

integrated circuits using digital tube displays "time", "sub",

"seconds" of modern design unit. If using digital circuits to

complete, the design of the circuit quite complex takes about 10

a few number of Manifold and its functions are mainly dependent on

the digital circuit a combination of the various functional blocks

to achieve the welding process is relatively complex and cost is

very high. If designed with the MCU to complete, due to the

realization of its functions mainly through software programming

to complete, then reduce the complexity of the hardware circuitry,

and its cost has decreased, so the use of the design used in

microcontroller AT89C51, it is a low - power, high-performance CMOS

8-bit microcontroller. AT89C51 microcontroller with seven-segment

display designed for simple timing alarm clock, you can set the

current time and display the alarm set-up time, if the time to sound

a while is issued, and further could expand the start-stop control

of electrical appliances.

Designed to include a second signal generator, the time display

circuit, key circuits, power supply and the alarm instruction

circuit design of several parts. Use of four switches to control the timing clock working state, respectively: K1, set the time and

clock hours: K2, set the hours and set the alarm switch: K3, set

the minute and alarm clock minutes: K4, is set to complete

withdrawal.

The figures do bell on SCM (AT89C51) at the core, Combined with

the componentsand factoring in the corresponding software, Easy to

produce digital clock purposes, as part of the hardware components

is a difficult choice, layout and welding.

Key words: Single Chip Microcomputer AT89C51

Atotal of anode LED digital tube display 目录

前言 ................................................................. 6

第一章 AT89C51单片机概述 ............................................ 7

1.1 AT89C51单片机的特点 .......................................... 7

1.2 AT89 C51单片机的引脚功能 ..................................... 7

第二章 总体方案设计............................................... 10

2.1 系统设计 .................................................... 10

2.1.1电路组成及工作原理 ......................................... 10

2.2 硬件系统 .................................................... 10

2.2.1单片机系统 ............................................. 10

2.3 时钟芯片的选择............................................... 11

3.1 输入部分 .................................................... 13

3.1.1电源模块 ............................................... 13

3.3 输出部分 .................................................... 15

3.3.1 显示模块............................................... 15

3.3.2 LED显示驱动 .......................................... 16