89C51单片机的c语言写的，用LED指示一个按键是长按还是短按，长按时候 不应该改变短按时候的 功能，从LED指示可以看出来-89C51 microcontroller c language written instructions of a button with LED is the long or short according to according to length by the short time should not be changed by the time the function of the instructions from the LED can be seen