Arduino Project

Smart Rain Cover

Course Introduction

In this lesson, you’ll build a simple display system using a potentiometer and an I2C LCD with the Arduino UNO R4.

By rotating the potentiometer, the Arduino reads the analog value and displays it on the LCD, along with a visual bar that represents the current position. The value is also printed to the serial monitor in real time.

Note

If this is your first time working with an Arduino project, we recommend downloading and reviewing the basic materials first.

1.1 Install Arduino IDE(Important)
1.2 Introduction of Arduino IDE

Required Components

In this project, we need the following components:

SN

COMPONENT INTRODUCTION

QUANTITY

PURCHASE LINK

1

Arduino UNO R4 Minima/Arduino UNO R4 WIFI

1

BUY

2

USB Type-C cable

1

×

3

Breadboard

1

BUY

4

Wires

Several

BUY

5

I2C LCD 1602

1

BUY

6

Potentiometer Sensor Module

1

BUY

Wiring

potentiometer_value.webp__PID:98d0da3f-4a00-4ad1-9411-609cea5e63e5

Common Connections:

Potentiometer Sensor Module
OUT: Connect to A0 on the Arduino.
GND: Connect to breadboard’s negative power bus.
VCC: Connect to breadboard’s red power bus.

I2C LCD 1602
SDA: Connect to A4 on the Arduino.
SCL: Connect to A5 on the Arduino.
GND: Connect to breadboard’s negative power bus.
VCC: Connect to breadboard’s red power bus.

Writing the Code

Note
You can copy this code into the Arduino IDE.
To install the library, use the Arduino Library Manager and search for LiquidCrystal I2C and install it.
Don’t forget to select the board(Arduino UNO R4) and the correct port before clicking the Upload button. 


/*
This Arduino code reads the value from a potentiometer connected to analog pin A0.
The read value is then displayed on an LCD 1620 with an I2C interface.
Additionally, the value is sent to the serial monitor. The LCD also displays a bar
corresponding to the potentiometer's value.

Board: Arduino Uno R4 (or R3)
Component:  Liquid Crystal Display 1620 with I2C Interface and Potentiometer module
Library: https://www.arduino.cc/reference/en/libraries/liquidcrystal-i2c/ (LiquidCrystal I2C by Frank de Brabander)
*/

// Required libraries for I2C and LCD operations
#include 
#include 

// Initialize LCD at I2C address 0x27 with 16 columns and 2 rows
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Variables to hold the potentiometer readings
int lastRead = 0;     // Previous potentiometer value
int currentRead = 0;  // Current potentiometer value

void setup() {
lcd.init();          // Initialize the LCD
lcd.backlight();     // Turn on the LCD backlight
Serial.begin(9600);  // Start serial communication at 9600 baud rate
}

void loop() {
// Read the current potentiometer value
int currentRead = analogRead(A0);

// Map the read value from 0-1023 to 0-16
int barLength = map(currentRead, 0, 1023, 0, 16);

// Update LCD only if the difference between current and last reading is greater than 2 to avoid jitter
if (abs(lastRead - currentRead) > 2) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Value:");
    lcd.setCursor(7, 0);
    lcd.print(currentRead);
    Serial.println(currentRead);

    // Display a bar on the second row of LCD proportional to the potentiometer value
    for (int i = 0; i < barLength; i++) {
    lcd.setCursor(i, 1);
    lcd.print(char(255));
    }
}

// Update the last read value for the next iteration
lastRead = currentRead;

// Introduce a delay for a stable reading
delay(200);
}