Have you ever made a city out of Legos? I know i have built many of them but they all missed something... Traffic lights!
So i decided to make my very own traffic light setup from my arduino board.

Step 1: You Will Need:

You will need:

An arduino board
Red, Green and amber LED's
Three 220 Ohm Resistors

Optional:

Wire
and an Protoshield

Step 2: Get the Components

I assume you already have an adruino board, and maybe also a Protoshield.

You'll need the LED's and resistors

the 220 Ohm resistors are color coded so: Red, Red, Brown

Step 3: Hook Up to the Board

Since this is a really simple project we only need 3 digital pins and ground.

Put the LED's in the breadboard/protoboard and use the resistors to connect them to the digital pins,

Green to pin 8
Yellow to pin 9
and Red to pin 10

then connect all the negative pins of the LED's together and to ground.

Step 4: Upload the Code!

Again, since this is a really simple project the code is also simple,
just copy it from below and upload it to your board via USB.

int greenled = 8; //Led's and pins
int yellowled = 9;
int redled = 10;

void setup()
{
pinMode(greenled, OUTPUT); //Pinmodes of the leds
pinMode(yellowled, OUTPUT);
pinMode(redled, OUTPUT);
}

void loop()
{
digitalWrite(greenled, HIGH); //Green on for 5 seconds
delay(5000);
digitalWrite(greenled, LOW); //Green off, yellow on for 2 seconds
digitalWrite(yellowled, HIGH);
delay(2000);
digitalWrite(yellowled, LOW); //yellow off, red on for 5 seconds
digitalWrite(redled, HIGH);
delay(5000);
digitalWrite(yellowled, HIGH); //Yellow and red on for 2 seconds
delay(2000);
digitalWrite(redled, LOW); //Red and Yellow off
digitalWrite(yellowled, LOW);
}