Generating tone in IF statement? Beginner's Problems 2

Projects Programming
1

It's me again with another probably quite stupid mistake. I have a simple goal: Play a tone as long as a button is pressed. Here's the code:

void setup() {
  pinMode(8, OUTPUT);
  pinMode(2, INPUT);
}

void loop() {
  int a = digitalRead(2);
  if (a = HIGH) {
    tone(8, 500);
  }
  if (a = LOW) {
    noTone(8);
  }

}

When I upload this sketch, the piezo speaker starts to play the specified tone and never stops. Regardless of if I'm pressing the button or not. If I read the button state via the serial output like this:

void setup() {
  pinMode(8, OUTPUT);
  pinMode(2, INPUT);
  Serial.begin(9600);
}

void loop() {
  int a = digitalRead(2);
  Serial.println(a);
  if (a = HIGH) {
    tone(8, 500);
  }
  if (a = LOW) {
    noTone(8);
  }

}

The serial output shows 1 when I press the button and 0 when I don't, so I know I wired the button up correctly. I also tried using 1 and 0 instead of HIGH and LOW in the if statement. Didn't work either.

Again, I feel like I'm making a basic mistake. I'd appreciate your help, thanks!

2

Take a look at these statement:

  if (a = HIGH) {
    tone(8, 500);
  }
  if (a = LOW) {
    noTone(8);
  }

then check out the assignment operator versus a relational operator and see if you can find a difference.

3

econjack:
Take a look at these statement:

  if (a = HIGH) {

tone(8, 500);
  }
  if (a = LOW) {
    noTone(8);
  }




then check out the assignment operator versus a relational operator and see if you can find a difference.

As I suspected, another dumb mistake. Thank you very much!