Traffic Lights With Shift Registers

/*Road intersection with traffic lights and pedestrian crossing lights. Uses 2 shift registers to control
traffic lights and pedestrian crossing lights

This sketch was created by Gary Granai , July,2021.  www.steamtrainfo.com
Yoy are free to use and modify this sketch as long as everything in this comment
section remains intact and unchanged.

Traffic lights are on shift register 1 and the pedestrian crossing lights are on shift register 2

Main road, crossing road and pedestrian crossing LEDs are each on their own resistor boards.

You may choose the number and type lights you put on the intersection. For details and documentation see  https://steamtraininfo.com/arduino-projects/traffic-signals
 */

/*
Shift register pin connections
Shift Register 1 Controls Traffic Lights
Q0 Main Road Red    Q1 Main Road Yellow   Q2 Main Road Green
Q3 Crossing Road Red Q4 Crossing Road Yellow
Q5 Crossing Road Green

Shift Register 2 Controls Pedestrian Crossing Lights
Q0 Main Road Pedestrian Red  Q1 Main Road Pedestrian Green
Q2 Crossing Road Pedestrian Red Q3 Crossing Road Pedestrian Green */




//Change these delays to change the timing of your traffic flow.

#define redDelay 5000
#define yellowDelay 450
#define maingreenDelay 7000
#define crossinggreenDelay 5000
#define redyellowDelay 350

//Pin connected to DS of 74HC595
#define dataPin 10
//Pin connected to ST_CP of 74HC595
#define latchPin 11
//Pin connected to SH_CP of 74HC595
#define clockPin 12

//***************************************************

void setup() {

//set pins to output so you can control the shift register
pinMode(latchPin, OUTPUT);
pinMode(clockPin, OUTPUT);
pinMode(dataPin, OUTPUT);

Serial.begin(9600);

}
//************************************************

void loop()  {

//Main road traffic flow, cross road traffic stopped

digitalWrite(latchPin, LOW);
//Pedestrian lights
shiftOut(dataPin, clockPin, MSBFIRST, B00001001);
//Traffic lights
shiftOut(dataPin, clockPin, MSBFIRST, B00001100);

digitalWrite(latchPin, HIGH);

delay(maingreenDelay);

//*********************************************

//pedesrian lights flash warning

/*begin for function.  This flashes 8 times.  Change
that and the delay to fit your intersection.*/


for(int i = 0; i < 7; i++){
digitalWrite(latchPin, LOW);
//Pedestrian lights
shiftOut(dataPin, clockPin, MSBFIRST, B00001001);
//Traffic lights
shiftOut(dataPin, clockPin, MSBFIRST, B00001110);
digitalWrite(latchPin, HIGH);
delay(yellowDelay);

digitalWrite(latchPin, LOW);

//Pedestrian lights
shiftOut(dataPin, clockPin, MSBFIRST, B00000001);
//Traffic lights
shiftOut(dataPin, clockPin, MSBFIRST, B00001110);
digitalWrite(latchPin, HIGH);

delay(yellowDelay);
}
//end for function

//************************************************

//all traffic stopped

digitalWrite(latchPin, LOW);
//Pedestrian lights
shiftOut(dataPin, clockPin, MSBFIRST, B00000101);

//Traffic lights
shiftOut(dataPin, clockPin, MSBFIRST, B00001001);
digitalWrite(latchPin, HIGH);
delay(redDelay);

//************************************************

//Change active lanes. Traffic starts on crossing road
//red yellow flash
digitalWrite(latchPin, LOW);
//Pedestrian lights
shiftOut(dataPin, clockPin, MSBFIRST, B00000101);
//Traffic lights
shiftOut(dataPin, clockPin, MSBFIRST, B00011001);
digitalWrite(latchPin, HIGH);
delay(redyellowDelay);



//Pedestrian lights
digitalWrite(latchPin, LOW);
shiftOut(dataPin, clockPin, MSBFIRST, B00000110);
//Traffic lights
shiftOut(dataPin, clockPin, MSBFIRST, B00100001);
digitalWrite(latchPin, HIGH);

delay(crossinggreenDelay);

//******************************************************

//pedesrian lights flash warning
/*begin for function.  This flashes 8 times.  Change
that and the delay to fit your intersection.*/

for(int i = 0; i < 7; i++){
digitalWrite(latchPin, LOW);
//Pedestrian lights
shiftOut(dataPin, clockPin, MSBFIRST, B00000110);
//Traffic lights
shiftOut(dataPin, clockPin, MSBFIRST, B00110001);
digitalWrite(latchPin, HIGH);
delay(yellowDelay);


digitalWrite(latchPin, LOW);
//Pedestrian lights
shiftOut(dataPin, clockPin, MSBFIRST, B00000100);
//Traffic lights
shiftOut(dataPin, clockPin, MSBFIRST, B00110001);
digitalWrite(latchPin, HIGH);
delay(yellowDelay);

}   //end for function

//************************************************

//all traffic stopped


digitalWrite(latchPin, LOW);
//Pedestrian lights
shiftOut(dataPin, clockPin, MSBFIRST, B00000101);
//Traffic lights
shiftOut(dataPin, clockPin, MSBFIRST, B00001001);
digitalWrite(latchPin, HIGH);
delay(crossinggreenDelay);


digitalWrite(latchPin, LOW);
//Pedestrian lights
shiftOut(dataPin, clockPin, MSBFIRST, B00000101);
//Traffic lights
shiftOut(dataPin, clockPin, MSBFIRST, B00001011);
digitalWrite(latchPin, HIGH);
delay(redyellowDelay);
}

//*****************************************************

/*The active traffic lane will now change as program loops
to beginning.*/