Arduino Nano ESP32 - Potentiometer LED
This tutorial instructs you how to use Arduino Nano ESP32 with the potentiometer to change the brightness of LED.
Hardware Preparation
| 1 | × | Arduino Nano ESP32 | |
| 1 | × | USB Cable Type-C | |
| 1 | × | Potentiometer | |
| 1 | × | LED | |
| 1 | × | 220 ohm resistor | |
| 1 | × | Breadboard | |
| 1 | × | Jumper Wires | |
| 1 | × | (Optional) DC Power Jack | |
| 1 | × | (Recommended) Screw Terminal Adapter for Arduino Nano |
Or you can buy the following sensor kits:
| 1 | × | DIYables Sensor Kit (30 sensors/displays) | |
| 1 | × | DIYables Sensor Kit (18 sensors/displays) |
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Overview of LED and Potentiometer
We have specific tutorials about LED and potentiometer. Each tutorial contains detailed information and step-by-step instructions about hardware pinout, working principle, wiring connection to ESP32, Arduino Nano ESP32 code... Learn more about them at the following links:
Wiring Diagram
This image is created using Fritzing. Click to enlarge image
How To Program
- Reads the input on analog pin (value between 0 and 4095)
int analogValue = analogRead(36); // GPIO36 (ADC0)
- Scales it to brightness (value between 0 and 255)
int brightness = map(analogValue, 0, 4095, 0, 255);
- Sets the brightness LED
analogWrite(LED_PIN, brightness);
Arduino Nano ESP32 Code
/*
* This Arduino Nano ESP32 code was developed by newbiely.com
*
* This Arduino Nano ESP32 code is made available for public use without any restriction
*
* For comprehensive instructions and wiring diagrams, please visit:
* https://newbiely.com/tutorials/arduino-nano-esp32/arduino-nano-esp32-potentiometer-led
*/
#define POTENTIOMETER_PIN A0 // The Arduino Nano ESP32 pin connected to Potentiometer pin
#define LED_PIN D3 // The Arduino Nano ESP32 pin connected to LED's pin
// the setup routine runs once when you press reset:
void setup() {
// initialize serial communication at 9600 bits per second:
Serial.begin(9600);
// declare LED pin to be an output:
pinMode(LED_PIN, OUTPUT);
}
// the loop routine runs over and over again forever:
void loop() {
// reads the input on analog pin A0 (value between 0 and 4095)
int analogValue = analogRead(POTENTIOMETER_PIN);
// scales it to brightness (value between 0 and 255)
int brightness = map(analogValue, 0, 4095, 0, 255);
// sets the brightness LED that connects to pin 3
analogWrite(LED_PIN, brightness);
// print out the value
Serial.print("Analog value = ");
Serial.print(analogValue);
Serial.print(" => brightness = ");
Serial.println(brightness);
delay(100);
}
Detailed Instructions
- If this is the first time you use Arduino Nano ESP32, see how to setup environment for Arduino Nano ESP32 on Arduino IDE.
- Copy the above code and paste it to Arduino IDE.
- Compile and upload code to Arduino Nano ESP32 board by clicking Upload button on Arduino IDE
- Open Serial Monitor on Arduino IDE
- Rotate the potentiometer
- See the LED fading
- See the result on Serial Monitor. It looks like the below:
COM6
Analog value = 6 => brightness = 1
Analog value = 34 => brightness = 8
Analog value = 89 => brightness = 22
Analog value = 149 => brightness = 37
Analog value = 214 => brightness = 53
Analog value = 297 => brightness = 74
Analog value = 365 => brightness = 90
Analog value = 431 => brightness = 107
Analog value = 510 => brightness = 127
Analog value = 589 => brightness = 146
Analog value = 695 => brightness = 173
Analog value = 790 => brightness = 196
Analog value = 970 => brightness = 241
Analog value = 996 => brightness = 248
Analog value = 1018 => brightness = 253
Analog value = 4095 => brightness = 255
Autoscroll
Clear output
9600 baud
Newline