Arduino How to Control Traffic Lights

2026-09-09 | By Ron Cutts

License: GNU Lesser General Public License LED Strips Microcontrollers PWM Serial / UART Arduino ESP32

In this tutorial, we will learn how to control traffic lights using Arduino and Visuino.
This tutorial is great for beginners.

Watch the video.

Learn more about Visuino: What is Visuino

What You Will Need

What You Will Need photo 2

What You Will Need photo 3

What You Will Need photo 4

What You Will Need photo 5

The Circuit

Connect "Traffic lights module" pin [GND] to Arduino pin[GND]
Connect "Traffic lights module" pin [R] to Arduino digital pin[2]
Connect "Traffic lights module" pin [Y] to Arduino digital pin[3]
Connect "Traffic lights module" pin [G] to Arduino digital pin[4]

The Circuit

Start Visuino, and Select the Arduino UNO Board Type

To start programming the Arduino, you will need to have the Arduino IDE installed from here: https://www.arduino.cc/.

Please be aware that there are some critical bugs in Arduino IDE 1.6.6. Make sure that you install 1.6.7 or higher; otherwise, this will not work! If you have not done so, follow the steps to set up the Arduino IDE to program Arduino UNO! The Visuino: https://www.visuino.eu also needs to be installed. Start Visuino as shown in the first picture. Click on the "Tools" button on the Arduino component (Picture 1) in Visuino. When the dialog appears, select "Arduino UNO" as shown in Picture 2

Start Visuino, and Select the Arduino UNO Board Type

Start Visuino, and Select the Arduino UNO Board Type photo 2

In Visuino ADD Components

Add "Sequence" component
Select "Sequence1" component and in the properties window set "Repeat" to: True, this will enable to repeat the whole process over and over meaning the lights will continue to flash
Double click on "Sequence1" component
in the "Elements" window drag 3X "Digital Period" to the left
On the left side of the "Elements" window select "Digital Period1" and in the properties window set "Delay" to 3000 <<This is the time after (3s) for the first light to flash
On the left side of the "Elements" window select "Digital Period2" and in the properties window set "Delay" to 6000 <<This is the time after start(6s) for the second light to flash
On the left side of the "Elements" window select "Digital Period3" and in the properties window set "Delay" to 9000 <<This is the time after start(9s) for the third light to flash
Close the "Elements" window

In Visuino ADD Components

In Visuino ADD Components photo 2

In Visuino ADD Components photo 3

In Visuino ADD Components photo 4

In Visuino ADD Components photo 5

In Visuino ADD Components photo 6

In Visuino Connect Components

Connect "Sequence1" > "Digital Period1" pin[Out] to Arduino board digital pin[2]
Connect "Sequence1" > "Digital Period2" pin[Out] to Arduino board digital pin[3]
Connect "Sequence1" > "Digital Period3" pin[Out] to Arduino board digital pin[4]

In Visuino Connect Components

Generate, Compile, and Upload the Arduino Code

In Visuino, at the bottom click on the "Build" Tab, make sure the correct port is selected, then click on the "Compile/Build and Upload" button.

Generate, Compile, and Upload the Arduino Code

Play

If you power the Arduino UNO module, the traffic lights module will start to change colors in a sequence.

Congratulations! You have completed your project with Visuino. Also attached is the Visuino project that I created for this. You can download it and open it in Visuino: https://www.visuino.eu