I need help I keep getting 0 cm

Other Hardware Sensors
1

int redLED = 2;
int greenLED = 3;
int blueLED = 4;
#define trigPin 5
#define echoPin 6

long duration;
int distance;

void setup() {
pinMode(redLED, OUTPUT);
pinMode(greenLED, OUTPUT);
pinMode(blueLED, OUTPUT);
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);
Serial.begin(9600);
}
void loop() {

duration = pulseIn(echoPin, HIGH);
distance = (duration/2) / 29.1;
Serial.print("Distance: ");
Serial.print(distance);
Serial.println(" cm");

if(distance <5){
digitalWrite(trigPin, HIGH);
digitalWrite(redLED, HIGH);
digitalWrite(greenLED, LOW);
digitalWrite(blueLED, LOW);
delayMicroseconds(10);
}

else if(distance >5 && distance <10){
digitalWrite(trigPin, HIGH);
digitalWrite(redLED, LOW);
digitalWrite(greenLED, HIGH);
digitalWrite(blueLED, LOW);
delayMicroseconds(10);
}

else if(distance >10 && distance <15){
digitalWrite(trigPin, HIGH);
digitalWrite(redLED, LOW);
digitalWrite(greenLED, LOW);
digitalWrite(blueLED, HIGH);
delayMicroseconds(10);
}

}

2

Hi,
To add code please click this link;

Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?
Hand drawn and photographed is perfectly acceptable.
Please include ALL hardware, power supplies, component names and pin labels.

What model Arduino are you using?

Have you looked at NewPing library to simplify your distance measurement?
https://playground.arduino.cc/Code/NewPing/

Tom.. :smiley: :+1: :coffee: :australia:

3

Suggest you add a couple of lines, as follows:

duration = pulseIn(echoPin, HIGH);
Serial.print("Duration: "); //new
Serial.println(duration); //also new
distance = (duration/2) / 29.1;
Serial.print("Distance: ");
Serial.print(distance);
Serial.println(" cm");

Then, look at the output, see if your calculation is correct.

4

You have to pulse the Trigger pin before you can measure the length of the Echo pulse.

You can do that with:

void loop() {
  digitalWrite(trigPin, HIGH);
  digitalWrite(trigPin, LOW);

  duration = pulseIn(echoPin, HIGH);
5

This topic was automatically closed 180 days after the last reply. New replies are no longer allowed.