【精品】基于单片机密码锁毕业设计论文.doc

毕业设计（论文） 基于单片机的电子密码锁设计 The Design of Electronic Password-lock with SCM  摘 要 随着电子产品向智能化和微型化的不断发展，单片机已成为电子产品研制和开发中首选的控制器。随着人们生活水平的提高，如何实现家庭防盗这一问题也变的尤其的突出，传统的机械锁由于其构造的简单，低功耗CMOS型E2PROMAbstract As electronic products are developing towards intelligence and minimization, single—chip computers (SCM ) have become the first choice for controllers in the development of electronic products. With the improvement of peoples living standards, it has become particularly prominent about how to achieve Anti-theft family. The traditional mechanical lock has such shortcoming as simple structure , Low security, it cant meet peoples demands. For practicality, this paper designs a new electronic cipher lock, which has the function of alarm and whose cipher can be changed many times. This cipher lock uses AT89S51 SCM and E2PROM AT24C02 as main chip and data memory cell . The author made this ciphor lock by use of making controlled program of master CMOS with periphery electrocircuit of keyboard input, display, alarm and unlock. Experiments show that the designed cipher lock is characterized by its reasonable designing methods, simple operation, low cost and property of safety and practicality．Besides，it works well as a residence lock and has great potential for comercial development．Key words: Cipher lock SCM Alarm  目 录 1 引言 1 1.1 电子密码锁简介 1 1.2 电子密码锁的发展趋势 1 1.3 本设计所要实现的目标 2 2 设计方案的选择 3 2.1 方案一：采用数字电路控制 3 2.2 方案二：采用以单片机为核心的控制方案 3 3 主要元器件介绍 4 3.1 主控芯片AT89S51 4 3.2 存储芯片AT24C02 9 3.3 LCD1602显示器 10 3.4 晶体振荡器 12 4 系统硬件构成 13 4.1 设计原理 13 4.2 电路总体构成 13 4.3 电源输入部分 14 4.4 键盘输入部分 15 4.5 密码存储部分 15 4.6 复位部位 16 4.7 晶振部分 17 4.8 显示部分 18 4.9 报警部分 18 4.10 开锁部分 19 5 系统软件设计 20 6 结论 24 谢辞 25 参考文献： 25 附录一 27 附录二 45 1 引言 1.1 电子密码锁简介 电子密码锁是一种通过密码输入来控制电路或是芯片工作，从而控制机械开关的闭合，完成开锁、闭锁任务的电子产品。它的种类很多，有简易的电路产品，也有基于芯片的性价比较高的产品。现在应用较广的电子密码锁是以芯片为核心，通过编程来实现的。其性能和安全性已大大超过了机械锁保密性好编码量多远远大于弹子锁。随机开锁成功率几乎为零。2密码可变用户可以更改密码，防止密码被盗，同时也可以避免因人员的更替而使锁的密级下降。3误码输入保护当