This tutorial of Robo India explains how to use RGB LED on NodeMCU using Arduino IDE.
Detailed Tutorial
1. Introduction:
An RGB LED is a combination of 3 LEDs RED, Green and Blue. These three colors Red, green and blue can make any color. By varying supplied voltage to RGB LEDs different colors are formed. In the Node MCU different voltage are supplied using analog output function.
An RGB LED has 4 pin interfaces. 3 Pins are for Red, Blue and Green. There is a common pins for all three LEDs
An RGB LED can be two types-
- Common Anode:-Anode (+) pin is common.
- Common Cathode:- (Cathode-/GND) pin is common.
1.1 Common Anode Type
1.2 Common Cathode Type
1.3 Hardware required
| S.No. | Item | Quantity |
| 1 | NodeMCU | 1 |
| 2 | Breadboard | 1 |
| 3 | RGB LED | 1 |
| 4 | Resistor 1k | 3 |
| 5 | Jumper Male to male | 6 |
2. Building Circuit
Schematic of circuit
Layout of circuit
3. Programming:
Once the circuit part is done, NodeMCU is needed to be programmed. Here is the code to run this circuit on NodeMCU.
You may download this code (Arduino Sketch) from here.
// Robo India Tutorial
// Digital Input and Output on LED
// Hardware: NodeMCU
const int RED = 5;
const int GREEN = 4;
const int BLUE = 0;
void setup() {
pinMode(RED, OUTPUT);
pinMode(GREEN, OUTPUT);
pinMode(BLUE, OUTPUT);
}
void loop() {
analogWrite(RED, 50);
analogWrite(GREEN, 50);
analogWrite(BLUE, 200);
delay (1000);
analogWrite(RED, 100);
analogWrite(GREEN, 100);
analogWrite(BLUE, 100);
delay (1000);
}
4. Output
After successful uploading of the code, the RGB LED generates two different colors in a time interval of 1 second. Try different set of RGB to get different colors.
5. Troubleshooting
LED is not glowing: LED may be common cathode type, pull it out and check it.
Generate new colors: Try new combination RGB values. The color will be from RGB palette.
If you have any query please write us at support@roboindia.com
Thanks and Regards
Content Development Team
Robo India
https://roboindia.com