3-Color Traffic Light LED

This is a module using three LEDs in the form of a traffic light: Red, Yellow, and Green.

Specifications

• Operating Voltage: 5V
• Operating Current: 20mA for each LED

Required Hardware

• 3-Color Traffic Light LED module
• Arduino UNO
• UNO Cable
• F-M Cable (4 pieces)

Connection

For the RYG terminals, you can set any pin number you want as OUTPUT to use.

3-Color Traffic Light LED	Arduino UNO
GND	GND
R	D3
Y	D4
G	D5

Example Code

// Define the pin numbers.
#define ledR 3
#define ledY 4
#define ledG 5

void setup()
{
    // Set the pins to OUTPUT.
    pinMode(ledR, OUTPUT);
    pinMode(ledY, OUTPUT);
    pinMode(ledG, OUTPUT);
}

void loop()
{
    // Create the LED lighting loop.
    // Lighting sequence (R -> off -> Y -> off -> G -> off -> All on -> All off)
    turnON(3);
    delay(500);
    turnOFF(3);
    delay(500);
    turnON(4);
    delay(500);
    turnOFF(4);
    delay(500);
    turnON(5);
    delay(500);
    turnOFF(5);
    delay(500);
    turnON(1);
    delay(500);
    turnOFF(1);
    delay(500);
}

// Function to turn the LED on.
void turnON(int x)
{
    // Operate 3,4,5 for R,Y,G respectively, and 1 turns all LEDs on.
    if (x == 3)
    {
        digitalWrite(ledR, HIGH);
    }
    else if (x == 4)
    {
        digitalWrite(ledY, HIGH);
    }
    else if (x == 5)
    {
        digitalWrite(ledG, HIGH);
    }
    else if (x == 1)
    {
        digitalWrite(ledR, HIGH);
        digitalWrite(ledY, HIGH);
        digitalWrite(ledG, HIGH);
    }
}

// Function to turn the LED off.
void turnOFF(int x)
{
    // Operate 3,4,5 for R,Y,G respectively, and 1 turns all LEDs off.
    if (x == 3)
    {
        digitalWrite(ledR, LOW);
    }
    else if (x == 4)
    {
        digitalWrite(ledY, LOW);
    }
    else if (x == 5)
    {
        digitalWrite(ledG, LOW);
    }
    else if (x == 1)
    {
        digitalWrite(ledR, LOW);
        digitalWrite(ledY, LOW);
        digitalWrite(ledG, LOW);
    }
}