可调闹钟倒计时器，数码管显示倒计时值，我很早以前写的，看对你们有没有帮助，就是用按键确定倒计时的时间，然后再倒计时，时间到后报警-Adjustable alarm clock countdown, I wrote long ago, there is no help for you to see, is to use keys to determine the countdown time, and then the countdown, time after the alarm