#include <AT89X51.h> //預處理命令

void main(void) //主函數名
{
  unsigned int a; //定義變量a為unsigned int類型
unsigned char b; //定義變量b為unsigned char類型

  do
		{ //do while組成循環
			for (a=0; a<65535; a++)
				P1_0 = 0; //65535次設P1.0口為低電平，點亮LED
			P1_0 = 1; //設P1.0口為高電平，熄滅LED

			for (a=0; a<30000; a++); //空循環

			for (b=0; b<255; b++)
				P1_1 = 0; //255次設P1.1口為低電平，點亮LED
			P1_1 = 1; //設P1.1口為高電平，熄滅LED


			for (a=0; a<30000; a++); //空循環
		}
	while(1);
}