hcsr04_lcd.ino

hcsr04_lcd.ino

#include <LiquidCrystal.h>
LiquidCrystal lcd(3, 4, 5, 6, 7, 8);

int Trig = 9;
int Echo = 10;
int Duration;
float Distance;

void setup() {
  Serial.begin(9600);

  pinMode(Trig,OUTPUT);
  pinMode(Echo,INPUT);
  lcd.begin(16, 2);
}

void loop() {
  digitalWrite(Trig,LOW);
  delayMicroseconds(1);
  digitalWrite(Trig,HIGH);
  delayMicroseconds(11);
  digitalWrite(Trig,LOW);
  Duration = pulseIn(Echo,HIGH);
  if (Duration>0) {
    Distance = Duration/2;
    Distance = Distance*340*100/1000000; // ultrasonic speed is 340m/s = 34000cm/s = 0.034cm/us 
    Serial.print(Duration);
    Serial.print(" us ");
    Serial.print(Distance);
    Serial.println(" cm");
    lcd.setCursor(0,0);
    lcd.print(Distance);
    lcd.setCursor(6,0);
    lcd.print("cm");
  }
  delay(500);
}