Introduction: Arduino Traffic Light Controller Using RBG Led | 4-Way

In this post, you are going to learn about how to make an Arduino traffic light controller. This traffic light controller will be used to control the flow of traffic. These can be applied in high traffic areas to avoid traffic blocks or accidents.

This project is done to give you an idea of how the traffic light controller works. This is not the real-time traffic light controller. So at the start, the red light of signal 1 and red lights at other signals will light up to give time to the vehicles at signal 1 to pass. After 5 seconds, the yellow light at signal 1 will light up to give an indication that the red light at signal 1 is about to come up and also to give an indication to the vehicles at signal 2 that the green light is about to light up. So after 2 seconds, red light at signal 1 will come up and green light at signal will come up meaning vehicles at signal 1 must stop and vehicles at signal 2 can move. Similarly, the traffic light controller will work for signal 3, signal 4 and the system will keep looping.

Step 1: Components Required:

1. Arduino Uno

2. RGB led*4

3. Breadboard

4. Resistor*12(220 ohms)

Step 2: Circuit Diagram:

There is a total of 4 RGB LEDs used in this project. Each signal has 1 RGB led (Red, Blue and Green) connected to it through the 220-ohm resistors. Using the colour combination I have made a yellow colour for the signal.

The resistors are used to limit the current that is going to pass through the LEDs. If you won’t use the resistors then the LEDs may burn due to excessive current.

Step 3: Code:

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