int LED1[] = {13,12,11};
int LED2[] = {3,2,35};
int LED3[] = {18,19,20};
int LED4[] = {29,31,33};
int reddelay =    5000;
int yellowdelay = 3000;
int greendelay =  5000;
int testTimer = 1000;
int walkDelay = 3000;
const int interruptPin21 = 21 ;
volatile bool isButtonPressed21 = false;
//
void button_pressed21()
{
   //Serial.println(isButtonPressed21);
   isButtonPressed21 = true;
   //Serial.println(isButtonPressed21);
   Serial.println("button is SET");
   //
}

void ledTesting()
{
 for (int i = 0; i < 3 ; i= i+1)   
  {   
    digitalWrite(LED1[i], HIGH);
    digitalWrite(LED2[i], HIGH);
    digitalWrite(LED3[i], HIGH);
    digitalWrite(LED4[i], HIGH);
    delay(testTimer);
    digitalWrite(LED1[i], LOW);
    digitalWrite(LED2[i], LOW);
    digitalWrite(LED3[i], LOW);
    digitalWrite(LED4[i], LOW);
    delay(testTimer);
    

  } 
}
void setup()
{
  Serial.begin(9600);
   pinMode(interruptPin21, INPUT_PULLUP);
   attachInterrupt(digitalPinToInterrupt(interruptPin21), button_pressed21, LOW);
   //pin#, ISR, Mode
   Serial.println("BEGIN");
   //
 for (int i = 0; i < 3 ; i= i+1)   
  {   
    pinMode(LED1[i], OUTPUT);
    pinMode(LED2[i], OUTPUT);
    pinMode(LED3[i], OUTPUT);
    pinMode(LED4[i], OUTPUT);
  }
  ledTesting();
}
void loop() 
{
  //done
  digitalWrite(LED1[2], HIGH); // LED1 red light on 
  digitalWrite(LED2[0], HIGH); // LED2 green  light on 
  digitalWrite(LED3[2], HIGH); // LED3 red light on 
  digitalWrite(LED4[0], HIGH); // LED4 green light on 
  delay(greendelay);
//done
  digitalWrite(LED1[2], HIGH); // LED1 red light on 
  digitalWrite(LED2[1], HIGH); // LED2 yellow light on 
  digitalWrite(LED3[2], HIGH); // LED3 red light on
  digitalWrite(LED4[1], HIGH); // LED4 yellow light on 
  digitalWrite(LED2[0], LOW); // LED2 green light off
  digitalWrite(LED4[0], LOW); // LED4 green light off
  delay(yellowdelay);
  //done
  digitalWrite(LED2[2], HIGH);  // LED2 red light on 
  digitalWrite(LED4[2], HIGH);  // LED4 red light on
  digitalWrite(LED2[1], LOW);   // LED2 yellow light off 
  digitalWrite(LED4[1], LOW);   // LED4 yellow light off
  digitalWrite(LED1[2], LOW);   // LED1 red off 
  digitalWrite(LED3[2], LOW);   // LED3 red off
  digitalWrite(LED1[0], HIGH);  // LED1 green light on
  digitalWrite(LED3[0], HIGH);  // LED3 green light on
  delay(yellowdelay);
  //done
  digitalWrite(LED2[2], HIGH); // LED2 red light on 
  digitalWrite(LED4[2], HIGH); // LED4 red light on 
  digitalWrite(LED1[2], LOW); // LED1 red light off 
  digitalWrite(LED3[2], LOW); // LED3 red light off 
  delay(yellowdelay);
  //done
  digitalWrite(LED1[1], HIGH); // LED1 yellow light on 
  digitalWrite(LED3[1], HIGH); // LED3 yellow light on 
  digitalWrite(LED1[2], LOW); //  LED1 red light off
  digitalWrite(LED3[2], LOW); //  LED3 red light off
  digitalWrite(LED1[0], LOW); //  LED1 green light off
  digitalWrite(LED3[0], LOW); //  LED3 green light off 
  delay(yellowdelay);
  //done
  digitalWrite(LED2[2], LOW); //  LED2 red light off 
  digitalWrite(LED4[2], LOW); //  LED4 red light off
  digitalWrite(LED1[1], LOW); //  LED1 yellow light off
  digitalWrite(LED3[1], LOW); //  LED3 yellow light off
  //
  
    Serial.println("Button is RE-SET");
  if(isButtonPressed21 == true)
  {
    letsWalkFunction();
    /*
   //Serial.println(isButtonPressed18);
   
   Serial.println("if - Button is RE-SET");
   isButtonPressed21 = false;
   //
   digitalWrite(LED1[2], HIGH); // LED1 red light on 
   digitalWrite(LED3[2], HIGH); // LED3 red light on 
   digitalWrite(LED2[2], HIGH); // LED2 red light on 
   digitalWrite(LED4[2], HIGH); // LED4 red light on
   digitalWrite(LED2[0], LOW);  // LED2 green light off
   digitalWrite(LED4[0], LOW);  // LED4 green light off
  }
  */
}
}

void letsWalkFunction()
{
Serial.println("if letsWalkFunction - Button is RE-SET");
   isButtonPressed21 = false;
   //
digitalWrite(LED1[0], LOW); // LED1 Green light on 
digitalWrite(LED1[1], LOW); // LED1 Yellow light on
digitalWrite(LED1[2], HIGH); // LED1 Red light on 
 
digitalWrite(LED2[0], LOW); // LED1 Green light on 
digitalWrite(LED2[1], LOW); // LED1 Yellow light on
digitalWrite(LED2[2], HIGH); // LED1 Red light on 

digitalWrite(LED3[0], LOW); // LED1 Green light on 
digitalWrite(LED3[1], LOW); // LED1 Yellow light on
digitalWrite(LED3[2], HIGH); // LED1 Red light on 

digitalWrite(LED4[0], LOW); // LED1 Green light on 
digitalWrite(LED4[1], LOW); // LED1 Yellow light on
digitalWrite(LED4[2], HIGH); // LED1 Red light on 
delay(walkDelay);
//
digitalWrite(LED2[2], LOW); // LED2 red light off 
digitalWrite(LED4[2], LOW); // LED4 red light off 
}