#include LiquidCrystal lcd(7, 6, 5, 4, 3, 2); const int trigPin = 11; const int echoPin = 10; const int led = 13; void setup() { pinMode(trigPin, OUTPUT); pinMode(echoPin, INPUT); pinMode(led, OUTPUT); lcd.begin(16, 2); lcd.print ("Ultrasonic "); lcd.setCursor(0, 1); lcd.print ("Range Meter"); delay (5000); } long duration, r; float distance; void loop() { lcd.clear(); lcd.print("Distance in cm"); digitalWrite(trigPin, LOW); delayMicroseconds(2); digitalWrite(trigPin, HIGH); delayMicroseconds(10); digitalWrite(trigPin, LOW); duration = pulseIn(echoPin, HIGH); long r = 3.4 * duration / 2; float distance = r / 100.00; lcd.setCursor(0, 1); lcd.print(distance); delay (300); if(distance<10) { digitalWrite(led,HIGH); } else { digitalWrite(led,LOW); } delay(300); }