Arduino - Ultrasonic Sensor - LCD
Hardware Required
1 | × | Arduino UNO or Genuino UNO | |
1 | × | USB 2.0 cable type A/B | |
1 | × | LCD I2C | |
1 | × | Ultrasonic Sensor | |
n | × | Jumper Wires |
Please note: These are affiliate links. If you buy the components through these links, We may get a commission at no extra cost to you. We appreciate it.
About Ultrasonic Sensor and LCD
If you do not know about Ultrasonic sensor and LCD (pinout, how it works, how to program ...), learn about them in the following tutorials:
Wiring Diagram
Arduino Code
/*
* Created by ArduinoGetStarted.com
*
* This example code is in the public domain
*
* Tutorial page: https://arduinogetstarted.com/tutorials/arduino-ultrasonic-sensor-lcd
*/
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x3F, 16, 2); // I2C address 0x3F, 16 column and 2 rows
int trigPin = 9; // TRIG pin
int echoPin = 8; // ECHO pin
float duration_us, distance_cm;
void setup() {
lcd.init(); // initialize the lcd
lcd.backlight(); // open the backlight
pinMode(trigPin, OUTPUT); // config trigger pin to output mode
pinMode(echoPin, INPUT); // config echo pin to input mode
}
void loop() {
// generate 10-microsecond pulse to TRIG pin
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
// measure duration of pulse from ECHO pin
duration_us = pulseIn(echoPin, HIGH);
// calculate the distance
distance_cm = 0.017 * duration_us;
lcd.clear();
lcd.setCursor(0, 0); // start to print at the first row
lcd.print("Distance: ");
lcd.print(distance_cm);
delay(500);
}
Quick Steps
- Connect Arduino to PC via USB cable
- Open Arduino IDE, select the right board and port
On Arduino IDE, Go to Tools Manage Libraries

- Search “LiquidCrystal I2C”, then find the LiquidCrystal_I2C library by Frank de Brabander
- Click Install button to install LiquidCrystal_I2C library.
- Copy the above code and open with Arduino IDE
- Click Upload button on Arduino IDE to upload code to Arduino
- Put the sensor on hot and cold water, or grasp the sensor by your hand
- See the result in LCD



Image is developed using Fritzing. Click to enlarge image
If LCD displays nothing, see Troubleshooting on LCD I2C
Code Explanation
Read the line-by-line explanation in comment lines of source code!
Video Tutorial
We are considering to make the video tutorials. If you think the video tutorials are essential, please subscribe to our YouTube channel to give us motivation for making the videos.
The Best Arduino Starter Kit
See Also
Follow Us