Help with counting

Using Arduino Project Guidance
1

Total newby here starting out with Arduino and programming.
Using Arduino Uno
I do teach Automotive engineering and understand the principles of circuits and wiring etc.
I have build a sketch with three LED's as outputs and one mom pushbutton. The idea is to get the outputs to change each time the button is pressed and then reset.
push 1 = Red Led on
Push 2 = Blue LED on, rest off
Push 3 = Green LED on, rest off.
Push 4 = all off, reset.
So far I have this working, but.... When I switch to Green LED, the other two flash. I assume this is the sketch picking up the switch going from high back to low when I release it. Can I stop this flash?
Hope I have uploaded code right,
Thank you

Circuit layout
Circuit layout771×721 45.4 KB


```cpp
// this constant won't change:
const int buttonPin = 8;  // the pin that the pushbutton is attached to
const int ledPin1 = 7;    // the pin that the LED is attached to
const int ledPin2 = 6;    //second led pin number
const int ledPin3 = 5;    //Third led pin number

// Variables will change:
int buttonPushCounter = 0;  // counter for the number of button presses
int buttonState = 0;        // current state of the button
int lastButtonState = 0;    // previous state of the button

void setup() {
  // initialize the button pin as a input:
  pinMode(buttonPin, INPUT);
  // initialize the LED as an output:
  pinMode(ledPin1, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  pinMode(ledPin3, OUTPUT);
  // initialize serial communication:
  Serial.begin(9600);
}


void loop() {
  // read the pushbutton input pin:
  buttonState = digitalRead(buttonPin);

  // compare the buttonState to its previous state
  if (buttonState != lastButtonState) {
    // if the state has changed, increment the counter
    if (buttonState == HIGH)

    {
      // if the current state is HIGH then the button went from off to on:
      buttonPushCounter++;
      Serial.println("on");
      Serial.print("number of button pushes: ");
      Serial.println(buttonPushCounter);
      if (buttonPushCounter >= 4)  // max number of pushes before reset
      {
        Serial.println("The button has been pressed four times");
        Serial.println("resetting the counter");
        buttonPushCounter = 0;
      } else {
        // if the current state is LOW then the button went from on to off:
        Serial.println("off");
      }
    }
    // save the current state as the last state, for next time through the loop
    lastButtonState = buttonState;


    //after one push, turns on red led
    if (buttonPushCounter < 1 == 0) {
      digitalWrite(ledPin1, HIGH);
    } else {
      digitalWrite(ledPin1, LOW);
    }

    //after two pushes, turns on blue led and turn off red
    if (buttonPushCounter < 2 == 0) {
      digitalWrite(ledPin2, HIGH);
      digitalWrite(ledPin1, LOW);
    } else {
      digitalWrite(ledPin2, LOW);
    }

    //after 3 pushes turns on green led and turn off blue.
    if (buttonPushCounter < 3 == 0) {
      digitalWrite(ledPin3, HIGH);
      digitalWrite(ledPin2, LOW);
    } else {
      digitalWrite(ledPin3, LOW);
    }
  }
}
2

Welcome to the forum

Have you got a resistor keeping the input pin LOW when the button is not pressed ? If not, it is floating at an unknown voltage, maybe HIGH, maybe LOW. maybe changing ?

If not, then consider using INPUT_PULLUP in the pinMode() to turn on the built in pullup resistor. Change the wiring to take the pin LOW when the button is pressed and change the sketch to detect LOW as a button press

As to the sketch itself, lines like this are odd

if (buttonPushCounter < 1 == 0)

Why not just test the value of buttonPushCounter ?

3

Thanks for the advice. I have a resistor to keep it pulled down. I have uploaded an image of the diagram..........but I have also solved it.
This sketch is one I grabbed from somewhere and made kinda work, but it was using lines that I had to adapt.
A little more research led me to a different sketch that works perfectly for me, posted below on the good suggestion of UKHeliBob.
Thank you for your time.

4

For the benefit of others, please explain what the problem was and post the working sketch

5

Certainly, this is one I have found and adapted. Took a bit less time than adjusting the other.


```cpp
// this constant won't change:
const int buttonPin = 8;  // the pin that the pushbutton is attached to
const int ledPin1 = 7;    // the pin that the LED is attached to
const int ledPin2 = 6;    //second led pin number
const int ledPin3 = 5;    //Third led pin number

// Variables will change://
int ledState = 0;  // the current state of the LEDs
int buttonState;   // the latest stable state of the input pin

void setup() {
  pinMode(buttonPin, INPUT);
  pinMode(ledPin1, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  pinMode(ledPin3, OUTPUT);
}

void loop() {
  static int lastButtonState = LOW;  // the previous reading from the input pin
  // the following variables are long's because the time, measured in miliseconds,
  // will quickly become a bigger number than can be stored in an int.
  static unsigned long lastDebounceTime = 0;  // the last time the output pin was toggled
  const unsigned long debounceDelay = 50;     // the debounce time; increase if the output flickers

  int currentButtonState = digitalRead(buttonPin);
  if (currentButtonState != lastButtonState) {
    lastDebounceTime = millis();
    lastButtonState = currentButtonState;
  }

  if ((millis() - lastDebounceTime) > debounceDelay && currentButtonState != buttonState) {
    // We have a new and different stable button state
    buttonState = currentButtonState;
    if (buttonState == LOW) {
      // The new state is "Pressed"
      ledState++;
      if (ledState > 4)
        ledState = 1;  // After 4, go back to 1

      if (ledState == 1) {
        digitalWrite(ledPin1, HIGH);
        digitalWrite(ledPin2, LOW);
        digitalWrite(ledPin3, LOW);
      }

      if (ledState == 2) {
        digitalWrite(ledPin1, LOW);
        digitalWrite(ledPin2, HIGH);
        digitalWrite(ledPin3, LOW);
      }

      if (ledState == 3) {
        digitalWrite(ledPin1, LOW);
        digitalWrite(ledPin2, LOW);
        digitalWrite(ledPin3, HIGH);
      }

      if (ledState == 4) {
        digitalWrite(ledPin1, LOW);
        digitalWrite(ledPin2, LOW);
        digitalWrite(ledPin3, LOW);
      }
    }
  }
}

Eventually this will be used on a race car to control the fan speeds for the interior heater fan rather than LED's, similar to a 4 position switch in most cars but using a single mom switch.