LED Fading Project

This project demonstrates how to gradually fade an LED's brightness up and down using Pulse Width Modulation (PWM) on an Arduino.

Components Required

• Arduino board (e.g., Uno, Nano)
• LED
• 220-ohm resistor
• Breadboard
• Jumper wires

Circuit Diagram

1. Connect the longer leg (anode) of the LED to digital pin 9 on the Arduino.
2. Connect the shorter leg (cathode) of the LED to one end of the 220-ohm resistor.
3. Connect the other end of the resistor to the GND (ground) pin on the Arduino.

Code Explanation

Variables

• int led = 9;: This variable stores the pin number where the LED is connected.
• int brightness = 0;: This variable stores the current brightness level of the LED (from 0 to 255).
• int fadeAmount = 5;: This variable determines the amount by which the brightness will change each loop iteration.

Setup

• void setup(): The setup() function runs once when the program starts. Inside this function:
  • pinMode(led, OUTPUT);: This sets the led pin as an output pin, meaning it will be used to control the LED.

Loop

• void loop(): The loop() function runs continuously after setup(). Inside this function:
  • analogWrite(led, brightness);: This sets the LED's brightness using PWM. The value of brightness can range from 0 (completely off) to 255 (fully on).
  • brightness = brightness + fadeAmount;: This line increments or decrements the brightness value by fadeAmount to gradually change the LED's brightness.
  • if (brightness <= 0 || brightness >= 255) { fadeAmount = -fadeAmount; }: This checks if the brightness value has reached the maximum (255) or minimum (0) and reverses the direction of fading by changing the sign of fadeAmount.
  • delay(30);: This pauses the program for 30 milliseconds to create a smooth fading effect.

How to Use

1. Connect your Arduino board to your computer.
2. Open the Arduino IDE.
3. Copy and paste the provided code into a new sketch.
4. Upload the sketch to your Arduino board.
5. Watch the LED fade in and out continuously.

License

This project is open-source and available under the MIT License.

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Enjoy experimenting with PWM and LED fading effects!