以51系列单片机(AT89C51)为核心，配以相应硬件电路，实现密码的设置、存贮、识别和显示，完成密码锁的模拟。单片机接收键入的代码，并与存贮在数组code_ram[6]中的密码进行比较，如果密码正确将会显示OPEN，如果密码不正确，将显示NO，并且允许操作人员重新输入密码，最多可输入三次；如果三次都不正确，则单片将上锁，并显示LOCK。每次按键完成后，6个数码管将会闪烁显示“—”，表示单片机已经接收到了输入的数据。-51 Series single-chip microcomputer (AT89C51) as the core, with the appropriate hardware circuits to achieve the password settings, storage, identification, and show that the completion of the simulation locks. Single-chip type to receive the code, and stored in an array code_ram [6] to compare the password, will be displayed if the password is correct OPEN, if the password is not correct, will show NO, and allows the operator to re-enter the password, up to can enter three times　if three are not correct, single-chip will be locked and displays LOCK. Upon completion of each button, 6 LED display will be flashing "-" , said single-chip has received input data.