CODE FOR ULTRASONIC SENSOR

Ultra Sonic Sensor Hand Written


int trig=3;
int echo=2;
int led=9;

void setup()
{
  Serial.begin(9600);
  pinMode(trig,OUTPUT);
  pinMode(echo,INPUT);
  pinMode(led,OUTPUT);
}

void loop()
{
  int duration;
  int distance;
  digitalWrite(trig,HIGH);
  delay(1000);
  digitalWrite(echo,LOW);
  duration=pulseIn(echo,HIGH);
  distance= (duration/2) /29.1;
  Serial.print(distance);
  Serial.print("cm\n");
  delay(1000);
if (distance=13)
{
digitalWrite(led,HIGH);
}
}