Here is my code
#define westButton 3
#define eastButton 13
#define westRed 2
#define westYellow 1
#define westGreen 0
#define eastRed 12
#define eastYellow 11
#define eastGreen 10
#define yellowBlinkTime 500 // 0.5 seconds for yellow light blink
v boolean trafficWest = true; // west = true, east = false
w int flowTime = 10000; // amount of time to let traffic flow
x int changeDelay = 2000; // amount of time between color changes4 Arduino Workshop
©2013, John Boxall
void setup()
{
// setup digital I/O pins
pinMode(westButton, INPUT);
pinMode(eastButton, INPUT);
pinMode(westRed, OUTPUT);
pinMode(westYellow, OUTPUT);
pinMode(westGreen, OUTPUT);
pinMode(eastRed, OUTPUT);
pinMode(eastYellow, OUTPUT);
pinMode(eastGreen, OUTPUT);
// set initial state for lights - west side is green first
digitalWrite(westRed, LOW);
digitalWrite(westYellow, LOW);
digitalWrite(westGreen, HIGH);
digitalWrite(eastRed, HIGH);
digitalWrite(eastYellow, LOW);
digitalWrite(eastGreen, LOW);
}
void loop()
{
if ( digitalRead(westButton) == HIGH ) // request west>east traffic flow
{
if ( trafficWest != true )
// only continue if traffic flowing in the opposite (east) direction
{
trafficWest = true; // change traffic flow flag to west>east
delay(flowTime); // give time for traffic to flow
digitalWrite(eastGreen, LOW); // change east-facing lights from green
// to yellow to red
digitalWrite(eastYellow, HIGH);
delay(changeDelay);
digitalWrite(eastYellow, LOW);
digitalWrite(eastRed, HIGH);
delay(changeDelay);
for ( int a = 0; a < 5; a++ ) // blink yellow light
{
digitalWrite(westYellow, LOW);
delay(yellowBlinkTime);
digitalWrite(westYellow, HIGH);
delay(yellowBlinkTime);
}
digitalWrite(westYellow, LOW);
digitalWrite(westRed, LOW); // change west-facing lights from red to green
digitalWrite(westGreen, HIGH);