Hind – Traffic Light!

My idea was to make a traffic light with the red, yellow and green LEDs. I decided to use a single switch button that cycles between modes as well as a potentiometer that changes the LED activated.

In order to make the button that cycles between modes, I got a lot of help from https://gist.github.com/navillus5/6699360

The 3 modes of my traffic light:

1. All LEDS blinking
2. Potentiometer activates either of the red, yellow, and green LEDs when dialed to a specific point
3. Off

Overall I think I executed my idea well as everything I intended for the assignment works, however one small issue I ran into is that when switched to the 2nd mode, the LEDS are very dim. My best guess is that it has to do with the resistors but I haven’t tested out this theory as I don’t want to accidentally damage my LEDs.

My Code:

const int buttonPin = 3;
const int redLight = 9;
const int yellowLight = 6;
const int greenLight = 5;
unsigned long timer = 0;
bool onOff = LOW;
byte prevButtonState = LOW;
bool blinking = false;
byte buttonMode = 0;
bool traffic = false;

boolean currentState = LOW;
boolean lastState    = LOW;
boolean stateChange  = false;

int currentButton = 0;
int lastButton    = 2;

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  pinMode(redLight, OUTPUT);
  pinMode(yellowLight, OUTPUT);
  pinMode(greenLight, OUTPUT);
  digitalWrite(redLight, LOW);
  digitalWrite(yellowLight, LOW);
  digitalWrite(greenLight, LOW);
  pinMode(buttonPin, INPUT);
}

void loop() {
  currentState = debounceButton();
  stateChange = checkForChange(currentState, lastState);
  currentButton = getButtonNumber(lastButton, currentState, stateChange);
  lastState  = currentState;
  lastButton = currentButton;
  
  // put your main code here, to run repeatedly:
  int potValue = analogRead(A0);
  int mappedPotValue = map(potValue, 0, 1023, 0, 255);
  int constrainedPotValue = constrain(mappedPotValue, 0, 255);
  Serial.println(currentButton);
//  byte buttonState  = digitalRead(buttonPin);

  if (currentButton == 0) {
    blinking = true;
//    buttonMode = buttonMode + 1;
  }
  if (currentButton == 1) {
    blinking = false;
    traffic = true;
  }
  if (currentButton == 2) {
    traffic = false;
  }

  if (traffic == true) {
    if (constrainedPotValue > 170) {
       digitalWrite(redLight, HIGH);
       digitalWrite(yellowLight, LOW);
       digitalWrite(greenLight, LOW);
    }
    if (constrainedPotValue <= 170 && constrainedPotValue > 85) {
       digitalWrite(redLight, LOW);
       digitalWrite(yellowLight, HIGH);
       digitalWrite(greenLight, LOW);
    }
    if (constrainedPotValue <= 85) {
      digitalWrite(redLight, LOW);
      digitalWrite(yellowLight, LOW);
      digitalWrite(greenLight, HIGH);
    }
  }
  
  if (blinking == true) {
    if (millis() > timer) {
      onOff = !onOff;
      timer = millis() + 250;
      digitalWrite(redLight, onOff);
      digitalWrite(yellowLight, onOff);
      digitalWrite(greenLight, onOff);
    }
  } else {
    digitalWrite(redLight, LOW);
    digitalWrite(yellowLight, LOW);
    digitalWrite(greenLight, LOW);
  }
}

// FUNCTIONS

//debounce
boolean debounceButton()
{
  boolean firstCheck   = LOW;
  boolean secondCheck  = LOW;
  boolean current = LOW;  
  firstCheck  = digitalRead(buttonPin);
  delay(50);
  secondCheck = digitalRead(buttonPin);  
  if (firstCheck == secondCheck){
    current = firstCheck;
  }
  return current;
}


//checks for change
boolean checkForChange(boolean current, boolean last)
{
  boolean change;  
  if (current != last){
    change = true;
  }
  else {
  change = false;
  }  
  return change;
}

//gets button num
int getButtonNumber(int button, boolean state, boolean change)
{
  if (change == true && state == LOW){
    button++;
    if (button > 2){
      button = 0;
    }
    Serial.println(button);
  }
  return button;
}