Interfacing LED to Arduino UNO and controlling it Using arduino code

Abstract

In this article, a comprehensive step-by-step guide to interface an external LED with Arduino UNO board using arduino code. This articles lays the foundation for more advanced embedded system and IoT projects.

Pre-Request

• OS : Windows / Linux / Mac / Chrome
• Arduino IDE

Hardware Required

• Arduino UNO.
• LED.
• Resistors.
• BreadBoard.
• Mini USB Cable.
• Connecting wires.
• 5V DC power supply (Optional)

Connection Table

Code

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#define LED_1 8
#define LED_2 4

void setup() {
  // Initialize LED as output PIN
  pinMode(LED_1, OUTPUT);
  pinMode(LED_2, OUTPUT);

}

void loop() {
  // Turning ON External LED
  digitalWrite(LED_1, HIGH); // HIGH Logic
  digitalWrite(LED_2, LOW); // LOW Logic
  delay(2000);

  // Turning OFF External LED
  digitalWrite(LED_1, LOW);  // HIGH Logic
  digitalWrite(LED_2, HIGH); // LOW Logic
  delay(1000);

}

Code Explanation

Accessing LED's.

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#define LED_1 8
#define LED_2 4

void setup() {
  // Initialize LED as output PIN
  pinMode(LED_1, OUTPUT);
  pinMode(LED_2, OUTPUT);

}

• Define LED_1 to GPIO 8 & LED_2 to GPIO 4.
• GPIO pin 8 is configured as OUTPUT pin (Line number 6)
• GPIO pin 4 is configured as OUTPUT pin (Line number 7)

Controlling LED

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void loop() {
  // Turning ON External LED
  digitalWrite(LED_1, HIGH); // HIGH Logic
  digitalWrite(LED_2, LOW); // LOW Logic
  delay(2000);

  // Turning OFF External LED
  digitalWrite(LED_1, LOW);
  digitalWrite(LED_2, HIGH);
  delay(1000);

}

• Continuous loop for blinking led is achieved using loop method.
• digitalWrite(LED_1, HIGH) sets the value of GPIO 8 to HIGH or 1, it turns ON the LED-1. (line number 13)
• digitalWrite(LED_2, LOW) sets the value of GPIO 4 to LOW or 0, it turns ON the LED-2. (line number 14)
• Delay is achieved through delay(ms_value); method. (line number 15 & 20)
• digitalWrite(LED_1, LOW) sets the value of GPIO 8 to LOW or 0, it turns OFF the LED-1. (line number 18)
• digitalWrite(LED_2, HIGH) sets the value of GPIO 4 to HIGH or 1, it turns OFF the LED-2. (line number 19)

Simulation

Extras

Components details

• Arduino UNO Data Sheet

Modules / Libraries Used

NIL