function running ultrasonic sensor does not return value

Development Boards Arduino
1

I’m using HC-RS04 ( http://www.micropik.com/PDF/HCSR04.pdf ) ultrasonic sensor. I got a function off the web somewhere, and I need it to return a value so that the LEDS would turn on and off according to distance. however it does nothing when the distance is low enough to change LED.

  int trigPin = 11;
  int echoPin = 10;
  int dist;
  int LEDPinR = 9;
  int LEDPinG = 8;
  
void setup() {
  Serial.begin(9600);
  pinMode(LEDPinR, OUTPUT);
  pinMode(LEDPinG, OUTPUT);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
}

void loop() {
  ultrasound(trigPin,echoPin,dist);
  Serial.print(dist);
    if (dist < 10)
      {
        digitalWrite(LEDPinR, HIGH); 
        digitalWrite(LEDPinG, LOW);
      }
    else
      {
        digitalWrite(LEDPinG, HIGH);
        digitalWrite(LEDPinR, LOW);
      }

}


 int ultrasound(int trigPin, int echoPin, int distance)
      {
        int duration;
        digitalWrite(trigPin, HIGH);
        delayMicroseconds(1000);
        digitalWrite(trigPin, LOW);
        duration = pulseIn(echoPin,HIGH);
        distance = (duration/58);
        Serial.print(distance);
        Serial.println( " cm");
        delay(500);
        return distance;
      }

Please and Thank You.

2

You are not using the return value for ultrasound() in loop(). Either use it or pass dist by reference

/mike