Single chip C language programming: timer control traffic light

 /* Name: Timer controlled traffic light

        Note: After the east-west green light is on for 5 seconds, the yellow light flashes, and then the red light flashes 5 times.

        After the red light comes on, the north-south direction turns from red to green, and after 5 seconds the north-south direction lights flash yellow.

        After flashing 5 times, the red light turns on, and the east-west light turns on green, and so on.

*/

#include

#define uchar unsigned char

#define uint unsigned int

sbit RED_A=P0^0; //East-West direction indicator

sbit YELLOW_A=P0^1;

sbit GREEN_A=P0^2;

sbit RED_B=P0^3; //North-South direction indicator light

sbit YELLOW_B=P0^4;

sbit GREEN_B=P0^5;

//Delay multiple, number of flashes, operation type

variable

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

//Timer 0 interrupt function

void T0_INT() interrupt 1

{

TL0=-50000/256;

TH0=-50000%256;

switch(Operation_Type)

{

case 1: //The east-west green light and the north-south red light are on for 5 seconds

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) switch

Time_Count=0;

Operation_Type=2;

break; [page]

case 2: //The east-west yellow light starts flashing and the green light turns off

if(++Time_Count!=8) return;

Time_Count=0;

YELLOW_A=~YELLOW_A;GREEN_A=0;

if(++Flash_Count!=10) return; //Flash

Flash_Count=0;

Operation_Type=3;

break;  

Case 3: //The east-west red light and the north-south green light are on for 5 seconds

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) switch

Time_Count=0;

                                        Operation_Type=4;

break;

case 4: //The yellow light in the north-south direction starts flashing, and the green light turns off

if(++Time_Count!=8) return;

Time_Count=0;

                                        YELLOW_B=~YELLOW_B;GREEN_A=0;

                                        if(++Flash_Count!=10) return; //Flash

                                        Flash_Count=0;

                                        Operation_Type=1;

                                        break;

             }

      }

//Main program

void main()

{

TMOD=0x01; //T0 mode 1

IE=0x82;

TR0=1;

while(1);

}