本程序演示一个计数器的工作过程 用定时器定时0.1s,每0.1要计数器加1，并在数码管上显示，高位零不显示-This program demonstrates the working process of a counter from time to time with the timer 0.1s, plus one for every 0.1 to the counter, and digital tube display, high zero does not appear