在51单片机的一个引脚输出一个方波,频率为1HZ-2KHZ,要求用定时器来实现...答:include<reg52.h> include<types.h> INT8U code table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};INT16U i=0; ge, shi, bai, qian, num=0,a,b,cnt;sbit led =P1^0;sbit key1=P3^0;//按键加 sbit key2=P3^1;//按键减 /***延时函数***/ void delay...