#include<reg51.h>

#define uchar unsigned char

#define uint unsigned int

sbit RED_A=P0^0; //東西向指示燈

sbit YELLOW_A=P0^1;

sbit GREEN_A=P0^2;

sbit RED_B=P0^3; //南北向指示燈

sbit YELLOW_B=P0^4;

sbit GREEN_B=P0^5;

//延時(shí)倍數(shù)，閃爍次數(shù)，操作類型

變量

uchar Time_Count=0,Flash_Count=0,Operation_Type=1; 

//定時(shí)器 0 中斷函數(shù)

void T0_INT() interrupt 1

{

TL0=-50000/256;

TH0=-50000%256;

switch(Operation_Type)

{

case 1: //東西向綠燈與南北向紅燈亮 5s

RED_A=0;YELLOW_A=0;GREEN_A=1;

RED_B=1;YELLOW_B=0;GREEN_B=0;

if(++Time_Count!=100) return; //5s（100*50ms）切換

Time_Count=0;

Operation_Type=2; 

break; 

case 2: //東西向黃燈開(kāi)始閃爍，綠燈關(guān)閉

if(++Time_Count!=8) return;

Time_Count=0;

YELLOW_A=~YELLOW_A;GREEN_A=0;

if(++Flash_Count!=10) return; //閃爍

Flash_Count=0;

Operation_Type=3; 

break;   

case 3: //東西向紅燈與南北向綠燈亮 5s

RED_A=1;YELLOW_A=0;GREEN_A=0;

RED_B=0;YELLOW_B=0;GREEN_B=1;

if(++Time_Count!=100) return; //5s（100*50ms）切換

Time_Count=0;

                                        Operation_Type=4;