数字式时钟，时钟用4个数字以12小时格式显示，用一个小指示灯区别上下午，用几个按钮设定闹钟的初始时间和闹铃时间。是在S3C2410实验箱上实现的-Digital clock, digital clock with 4 to 12-hour format, with a small difference between morning and afternoon light, with a few buttons to set the alarm time and alarm time initi