本程序用到4x4按键中断扫描法，用lcd显示，开机时候显示一个数字钟（时间不可设，稍后加入该功能），钟正常走

如果按下开锁键，进入以请输入密码界面，输入密码，如果密码正确，显示欢迎使用，密码错误蜂鸣器报警

且LCD显示密码错误，请重新输入。

注：数字时钟用的是DS1302实现，由于本人也才学单片机一个多月，所以注释非常详细，初学者很容易看懂。-This procedure used key interrupt scanning 4x4, with lcd display, boot displays a digital clock time (time can not be set up later to join the function), follow the normal bell press the unlock button, if, in order to please enter a password to enter the interface, enter password, if the password is correct, display Welcome, password error buzzer alarm and LCD display the password error, please re-enter. Note: Digital Clock using DS1302 achieved, single-chip microcomputer as a result of talent and learning I have more than a month, so very detailed notes, a beginner can easily understand.