AT89C51单片机智能小区电子门控制系统的设计（毕业设计参考）

目    录

摘要.......................................................................................................................... II

Abstract................................................................................................................. III

1绪论....................................................................................................................... 1

1.1研究背景和意义..................................................................... 1

1.2国内外技术现状..................................................................... 1

1.3本课题的研究内容................................................................. 3

2 门控系统的硬件电路设计........................................................................... 4

2.1硬件电路整体结构................................................................. 4

2.2AT89C51单片机...................................................................... 5

2.2.1 51系列单片机................................................................................ 5

2.2.2 AT89C51单片机的特点及工作原理........................................... 6

2.3  可编程并行接口芯片8255A............................................. 10

2.3.1引脚说明....................................................................................... 11

2.3.2.工作方式选择............................................................................... 12

2.4键盘接口设计....................................................................... 13

2.4.1. 键盘输入的特点........................................................................ 13

2.4.2按键的确认................................................................................... 14

2.4.3.键盘接口....................................................................................... 14

2.4.4键盘的工作方式........................................................................... 18

2.5音频电路的设计................................................................... 19

2.5.1  LM324运算放大器.................................................................. 20

2.5.2 音频电路设计.............................................................................. 21

2.5.3 通话电路的控制......................................................................... 21

2.6开门继电器的驱动............................................................... 22

2.7电源部分设计....................................................................... 24

3系统软件的设计............................................................................................. 28

3.1 系统程序设计...................................................................... 28

3.1.1 程序设计的基本流程图............................................................. 28

4系统的抗干扰设计........................................................................................ 32

4.1 干扰的分类及抗干扰的几大原则...................................... 32

4.2 硬件抗干扰设计.................................................................. 32

4.3软件抗干扰设计................................................................... 33

5总结与展望....................................................................................................... 35

5.1 工作总结.............................................................................. 35

5.2 工作展望.............................................................................. 35

参考文献............................................................................................................... 36

附录A.................................................................................................................... 37

附录B.................................................................................................................... 38

致谢......................................................................................................................... 47

摘要

本文主要论述了智能小区电子门控制系统的基本原理、结构和设计过程。按照经济实用的原则，以每单元8户的标准，对智能小区电子门控制系统进行设计，系统主要包括处理器、访客端和住户端三大部分。控制系统的微处理器采用单片机，具体型号为Atmel公司的AT89C51。系统按模块化的思想进行设计，设计了访客端键盘部分、住户端键盘部分、音频电路部分，电源电路部分、继电器驱动部分和单片机复位部分。在本系统中，采用可编程并行接口芯片8255A对单片机进行I/O口的扩展，以满足系统众多接口的需要。设计中，每个住户端都配备通话键、开门键、麦克风和扬声器，访客端配备8个访问按钮、扬声器和麦克风，使住户可以与访客进行简单的交流，以方便住户确认访客的身份，这样的设计可以满足简单实用性的要求。

关键字：电子门；单片机；控制系统

Abstract

In this paper, intelligent electronic door control system is studied and discussed. At the end of the design, the feasibility of the circuit has been testified by the software of  Proteus. According to the principle of economic and function, on the basis of 8 household in every unit, the control system is designed to three main module include the microprocessor module, the host module and the guest module. The microprocessor adopt singlechip and the type is AT89C51 which come from Atmel. According to the thought of modularity, the circuit include the guest keyboard part, the host keyboard, the voice circuit part, the drive circuit of relay and the reset circuit of singlechip. To meet the demand of the system, the IC of 8255A is applied to expand the interface of AT89C51. In the system, every host part include conversation key, open key, microphone and loudspeaker. The guest part include 8 ring key, microphone and loudspeaker. The circuit can meet the demand of the conversation.

Keywords: electronic door; singlechip; control system