Arduino Project

RGB Controll

Course Introduction

In this lesson, you’ll learn how to use a potentiometer with the Arduino UNO R4 to control an RGB LED.

As you turn the knob, the LED color smoothly transitions through red, yellow, green, and blue, creating a dynamic color blending effect.

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

Potentiometer

1

BUY

6

RGB LED

1

BUY

Wiring

RGB_color_bb.png.webp__PID:523855e0-6573-40e0-a604-207130b702de

Common Connections:

RGB LED
R: Connect to 9 on the Arduino.
Y: Connect to 10 on the Arduino.
G: Connect to 11 on the Arduino.
GND: Connect to breadboard’s negative power bus.

Potentiometer
OUT: Connect to A0 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.
Don’t forget to select the board(Arduino UNO R4 Minima/WIFI) and the correct port before clicking the Upload button.


// RGB LED pins
const int redPin = 9;
const int greenPin = 10;
const int bluePin = 11;

// Potentiometer pin
const int potPin = A0;

void setup() {
  pinMode(redPin, OUTPUT);
  pinMode(greenPin, OUTPUT);
  pinMode(bluePin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  // Read potentiometer value (0–1023)
  int potValue = analogRead(potPin);
  Serial.println(potValue);

  // Map the potentiometer value to 0–765 range for color blending
  int range = map(potValue, 0, 1023, 0, 765);

  int r = 0, g = 0, b = 0;

  // Blend RGB colors based on range
  if (range <= 255) {
    r = 255;
    g = range;
    b = 0;
  } else if (range <= 510) {
    r = 510 - range;
    g = 255;
    b = range - 255;
  } else {
    r = 0;
    g = 765 - range;
    b = 255;
  }

  // Set RGB LED color
  analogWrite(redPin, 255 - r);   // Inverted for common cathode
  analogWrite(greenPin, 255 - g);
  analogWrite(bluePin, 255 - b);

  delay(20);
}