Traffic light system trouble

Using Arduino Programming Questions
1

Hello,I am new to programming and arduino. i have began a project that involves creating a double traffic light system that includes two sets of traffic lights, two push buttons for pedestrians and finally two sets of light for pedestrians. I have been working on this for a while now and have came to a dead end. its probably simple but i just cant get it.

I have the stop-go sequence of the lights working but when either of the push buttons are pressed, it must stop the sequence and the car lights must go red then the pedestrian lights can both go green. The trouble i am having is that i cant program it to change when the button is pressed, it just keeps continuing with the sequence.

I have tried many times starting from scratch but it always seems to end up as the same problem.

I have included my code below and sorry for any stupid mistakes and sorry that it is probably written very badly. As i said before i am new to this and any help would be greatly appreciated!

int carRed1 = 13; //car lights being assigned
int carAmber1 = 12;
int carGreen1 = 11;
int carRed2 = 10;
int carAmber2 = 9;
int carGreen2 = 8;
int walkRed1 = 7; //walking lights being assigned
int walkGreen1 = 6; 
int walkRed2 = 5;
int walkGreen2 = 4;
int button1 = 2; // button pins
int button2 = 3;
int crossTime = 10000;  //crossing time variable given to pedestrians
int flag = digitalRead(button1) or digitalRead(button2);

void setup() {
  pinMode(carRed1, OUTPUT);   //defining each pin mentioned as either input or output
  pinMode(carAmber1, OUTPUT);
  pinMode(carGreen1, OUTPUT);
  pinMode(walkRed1, OUTPUT);
  pinMode(walkGreen1, OUTPUT);
  pinMode(button1, INPUT);
  
  pinMode(carRed2, OUTPUT);
  pinMode(carAmber2, OUTPUT);
  pinMode(carGreen2, OUTPUT);
  pinMode(walkRed2, OUTPUT);
  pinMode(walkGreen2, OUTPUT);
  pinMode(button2, INPUT);

}

void checkCrossing()
{
  if(carRed1 == HIGH);{
    digitalWrite(carAmber1, LOW);
    digitalWrite(carGreen1, LOW);}
  if(carRed1 == LOW);{
   goRed1();}
   if(carRed2 == HIGH);{
    digitalWrite(carAmber1, LOW);
    digitalWrite(carGreen1, LOW);}
  if(carRed2 == LOW);{
   goRed2();}
}

void goRed1()
{
  delay(1000);
  digitalWrite(carGreen1, LOW);
  digitalWrite(carAmber1, HIGH);
  delay (2000);
  digitalWrite(carAmber1, LOW);
  digitalWrite(carRed1, HIGH);
}

void goRed2()
{
  delay(1000);
  digitalWrite(carGreen2, LOW);
  digitalWrite(carAmber2, HIGH);
  delay (2000);
  digitalWrite(carAmber2, LOW);
  digitalWrite(carRed2, HIGH);
}
void loop()
{
  while (flag == HIGH)
  {
    checkCrossing();
  }
  while (flag == LOW)
  {
  digitalWrite(walkRed1, HIGH);
  digitalWrite(walkRed2, LOW);
  digitalWrite(carRed1, LOW); 
  digitalWrite(carRed2, HIGH);
  digitalWrite(carAmber1, LOW);
  digitalWrite(carAmber2, LOW);
  digitalWrite(carGreen1, HIGH);
  digitalWrite(carGreen2, LOW);
  digitalWrite(walkGreen1,LOW);
  digitalWrite(walkGreen2, HIGH);
  

  delay(20000);

  digitalWrite(walkGreen2, LOW);
  digitalWrite(walkRed2, HIGH);
  digitalWrite(carGreen1, LOW);
  digitalWrite(carAmber1, HIGH);
  delay (2000);
  digitalWrite(carAmber1, LOW);
  digitalWrite(carRed1, HIGH);
  delay(2000);

  digitalWrite(carAmber2, HIGH);
  delay(2000);
  digitalWrite(carRed2, LOW);
  digitalWrite(carAmber2, LOW);
  digitalWrite(carGreen2, HIGH);
  digitalWrite(walkRed1, LOW);
  digitalWrite(walkGreen1, HIGH);

  delay(20000);

  digitalWrite(walkGreen1, LOW);
  digitalWrite(walkRed1, HIGH);
  digitalWrite(carGreen2, LOW);
  digitalWrite(carAmber2, HIGH);
  delay (2000);
  digitalWrite(carAmber2, LOW);
  digitalWrite(carRed2, HIGH);
  delay(2000);

  digitalWrite(carAmber1, HIGH);
  delay(2000);
  digitalWrite(carRed1, LOW);
  digitalWrite(carAmber1, LOW);

  }
}
2

Your program seems to depend on the value of the flag variable, but you only set its value once with this rather odd statement

int flag = digitalRead(button1) or digitalRead(button2);

Then you never check the inputs again

3

Thanks for the reply.

What would you suggest i do to change this then because i have tried just reading the state of each button in the while loop and it still doesn't work, i am so confused by this and it is probably simple to everyone else.

4

If it were me then I would use millis() to time the regular traffic light changes which would allow the buttons to be read each time through loop(). Once a button press was detected then I would set the lights appropriately and use millis() again to time how long the pedestrian state lasted before returning to the car state. See the BlinkWithoutDelay example in the IDE to see how to use millis() for timing without blocking the free running of the loop() function.

5 
void checkCrossing()
{
  if(carRed1 == HIGH);{
    digitalWrite(carAmber1, LOW);
    digitalWrite(carGreen1, LOW);}
  if(carRed1 == LOW);{
   goRed1();}
   if(carRed2 == HIGH);{
    digitalWrite(carAmber1, LOW);
    digitalWrite(carGreen1, LOW);}
  if(carRed2 == LOW);{
   goRed2();}
}

If; statements; rarely; have; semicolons;.