#include <reg51.h> #include <intrins.h> sbit s=P2^5; int i=200; void main() { TMOD=0x01; TH0=0xee; TL0=0x00; EA=1; ET0=1; TR0=1; P1=0xff; while(1); {;} } //定时器T0在方式1下循环满最大值为65.5ms,所以选择每50ms一循环,循环200次; void timer0() interrupt 1 { if(s==0){ TH0=0xee; TL0=0x00; i--; if(i<=0){ P1=~P1; i=200; } } }