Click Master: Arduino Reflex Game with LEDs, Buttons & TM1637 Display

Introduction

Click Master isn’t just an electronics project—it’s a fast-paced, precision-driven game that turns a handful of LEDs and buttons into a thrilling test of reflexes and focus.

From the moment the red LED begins to pulse and the word “RED” appears on the four-digit display, tension builds. Pressing the red button kicks off a countdown—3, 2, 1—and launches the player into a series of increasingly challenging levels where timing is everything.

The concept is simple: watch the rotation of colored LEDs (yellow, green, blue) and hit the red button exactly when the red LED lights up. Not a second too soon, not a moment too late. On the display, two numbers appear: the target count (randomly chosen between 10 and 30) and the current score. Behind the scenes, the system tracks each LED flash, and when the count hits the target, the red LED blinks briefly. If the player reacts within that narrow window, they earn a point. Miss it—or jump the gun—and the score drops. This balance between anticipation and control makes Click Master increasingly intense as the levels climb.

Reach level 50 with a perfect score, and the game rewards you with a short victory tune played through the speaker—a satisfying finale that adds charm and closure to the experience. Even if the score isn’t perfect, the final tally flashes before the game resets, ready for another round.

Whether you're running a STEM workshop, teaching electronics, or just love DIY tech, Click Master is a fantastic tool for exploring human-machine interaction. It’s affordable, easy to build, and endlessly expandable—add EEPROM score saving, new LED colors, sound effects, or even multiplayer features. It’s proof that tech can be both educational and fun.

In the end, Click Master shows that great games don’t need fancy graphics or complex mechanics. With a clear concept, smart design, and a bit of Arduino magic, it delivers a hands-on experience that lights up, plays music, and sharpens your reflexes in a way you won’t forget.

How to play "Click Master"

The game begins when the player presses the red button, prompted by the blinking red LED and the glowing “RED” text on the TM1637 display. This triggers a countdown—three seconds of rising tension, backed by sound effects. When the countdown hits zero, the display clears and the game enters active mode.

Each level challenges the player to track a rapid rotation of yellow, green, and blue LEDs. As they flash in sequence, the system silently counts each one. When the internal counter reaches the randomly selected target number, the red LED lights up suddenly, accompanied by a distinct audio cue.

This is the critical moment: the player must press the red button within a very short time frame. A well-timed press earns a point and a satisfying sound. A mistimed press—too early or too late—results in a penalty, a negative tone, and a brief blackout of the LEDs.

Throughout the game, the display shows both the current score and the target count, offering constant feedback. As the player progresses, the reaction window shrinks, turning each level into a high-speed challenge of reflex and anticipation.

At level 50, if the player hits the maximum score, the game celebrates with a short, harmonious melody and a flashing score display. After a few seconds, it resets to the “RED” screen, ready for the next attempt.

How to play "Click Master"

1. Game Start

Press the red button when prompted by the blinking LED and the “RED” display.
A countdown begins: 3, 2, 1, with sound effects.
When it ends, the screen clears and the game begins.

2. LED Sequence Challenge

LEDs flash in a fast, rhythmic rotation: yellow, green, blue.
The system counts each flash internally.
When the count reaches a randomly chosen target, the red LED lights up with a sound cue.

3. Reaction Window

Press the red button quickly when the red LED lights up.

✅ Correct timing: score increases, energizing sound plays.
❌ Mistimed press: score decreases, warning tone plays, LEDs turn off briefly.

4. Feedback and Difficulty

Display shows:
- Current score
- Target count for the round
As levels increase, the reaction time shortens, making the game progressively harder.

5. Game Finale

At level 50, if the player reaches the maximum score:
- A victory melody plays
- Final score flashes
Game resets to the “RED” screen, ready for a new challenge.

🔌 The Circuit Diagram

At first glance, the circuit diagram might look intimidating—its lines twisting and turning like a never-ending technical tale. But don’t let appearances discourage you. We’ll walk through it together, step by step, decoding each symbol and uncovering the logic behind the layout. As we place the components onto the breadboard in a clear and intuitive way, you’ll see how quickly confusion turns into curiosity—and curiosity into confidence.

Wiring Overview: Connecting the Circuit

As you can see, the circuit is built from a series of straightforward connections between the Arduino and various components. Each wire has a purpose, and together they form the backbone of the game’s interactive experience. Here's how everything links up:

🔴 Red Button & LED

Red Button Terminal 1 → Arduino Pin D12
Red Button Terminal 2 → Arduino GND
Arduino Pin D7 → Resistor R1 (Terminal 1, for Red LED)
Resistor R1 (Terminal 2) → Positive (+) leg of Red LED
Negative (−) leg of Red LED → Arduino GND

🟡 Yellow Button & LED

Yellow Button Terminal 1 → Arduino Pin D6
Yellow Button Terminal 2 → Arduino GND
Arduino Pin D10 → Resistor R2 (Terminal 1, for Yellow LED)
Resistor R2 (Terminal 2) → Positive (+) leg of Yellow LED
Negative (−) leg of Yellow LED → Arduino GND

🟢 Green Button & LED

Green Button Terminal 1 → Arduino Pin D8
Green Button Terminal 2 → Arduino GND
Arduino Pin D4 → Resistor R3 (Terminal 1, for Green LED)
Resistor R3 (Terminal 2) → Positive (+) leg of Green LED
Negative (−) leg of Green LED → Arduino GND

🔵 Blue Button & LED

Blue Button Terminal 1 → Arduino Pin D9
Blue Button Terminal 2 → Arduino GND
Arduino Pin D5 → Resistor R4 (Terminal 1, for Blue LED)
Resistor R4 (Terminal 2) → Positive (+) leg of Blue LED
Negative (−) leg of Blue LED → Arduino GND

🔊 Speaker

Positive (+) terminal of Speaker → Arduino Pin D12
Negative (−) terminal of Speaker → Arduino GND

🖥️ TM1637 Display

CLK (Terminal 1) → Arduino Pin D3
DIO (Terminal 2) → Arduino Pin D2
GND (Terminal 3) → Arduino GND
VCC (Terminal 4) → Arduino 5V

Materials Needed

Arduino Uno or a compatible equivalent board

4 LEDs (preferably 5mm) in different colors: red, yellow, green, and blue

4 momentary push buttons (normally open) that can be mounted on a breadboard

1 four-digit, seven-segment display controlled by a TM1637 driver chip

a speaker for sound feedback

1 large breadboard (830 tie-points recommended)

Jumper wires for all necessary connections

🛠️ Installing Components on the Breadboard

As you’ll notice, the number of electrical connections required is quite manageable. You just need to pay attention to a few key details to ensure everything is set up correctly:

LEDs are polarized components, meaning they must be connected in the correct direction. To help guide you, we’ve labeled the legs as A (anode, +) and K (cathode, −). If installed backwards, the LEDs won’t light up.

Push buttons have four pins arranged in a rectangular layout—not a perfect square. This means they naturally fit into the breadboard in only one orientation, without forcing them.

Resistors are non-polarized, so they can be placed in either direction. Their role is to limit current and protect sensitive components, especially the LEDs.
The speakers may come with colored wires. If the terminals aren’t marked, remember: the red wire typically indicates the positive side and should be connected to Pin D12, while the black wire goes to GND.
Breadboard power rails are grouped in sets of 25 pins along the sides. To ensure consistent voltage across the board, it’s important to bridge the power rails—this keeps the power supply uniform throughout the entire length of the breadboard.
If this is your first time using an Arduino board, you can connect everything without worry. A fresh board won’t have any preloaded programs, so there’s no risk of unexpected behavior during setup.

Source Code

Before compiling the source code, you’ll need to install a library that enables communication with the 4-digit, 7-segment display powered by the TM1637 driver chip. The library is called “TM1637”, developed by Avishay Orpaz.

To install it:

Open the Library Manager in the Arduino IDE
Search for “TM1637”
Select “TM1637 by Avishay Orpaz”
Click “INSTALL”

You can download the source code here. The file includes detailed comments explaining nearly every line, making it easy to follow and customize.

Note: The link opens a .ino file in a new browser tab. Since most browsers treat it as plain text, you’ll need to save it properly:

Press Ctrl + S
In the “Save as type” dropdown, choose “All files”
Add the .ino extension to the filename (e.g., clickMaster.ino). Alternatively, you can copy the entire code (Ctrl + A, then Ctrl + C), open a new sketch in the Arduino IDE, and paste it (Ctrl + V) directly.

Once your components are installed on the breadboard, simply upload the code to your Arduino board and enjoy the game! 🎮

If you feel the game is too slow or too fast for your taste, you can easily tweak the timing by modifying the following line of code:

int redDuration = map(nivel, 1, 50, 1000, 80);

This line controls how long the red LED stays lit at each level. Here's how it works:

1000 represents the duration in milliseconds at level 1—meaning the red LED stays on for 1 second.
80 is the duration at level 50, where the LED only stays lit for 80 milliseconds.
The transition between these two values is linear, gradually decreasing the reaction window as the player progresses.

Want to slow things down?

Try increasing the starting value:

int redDuration = map(nivel, 1, 50, 1500, 80);

Want a faster, more dynamic challenge?

Lower the starting value:

int redDuration = map(nivel, 1, 50, 700, 80);

And That’s Not All…

You can take this project to the next level by integrating all components into a custom enclosure. If you have access to a 3D printer, you can design an attractive and ergonomic case tailored to your layout and style.

No 3D printer? No problem — an ABS plastic box, commonly used in electrical installations, is a great alternative. It offers durability, safety, and a clean, professional appearance.

With a proper enclosure, your project gains not only functionality but also a presentation that truly stands out.

Explore the resources and design ideas here...

Bonus Update – Click Master Reimagined!

We've revamped Click Master, adding exciting new features that elevate it from a simple reflex test to a fast-paced, precision-driven challenge. Here's what's new and improved:

Precision-Based Scoring

+2 points for tapping during the first half of the red LED window
+1 point for tapping during the second half
−1 point for tapping too early, too late, or not at all

Accuracy Streak Bonus

Score +5 extra points for landing five perfect taps in a row (+2 each)
After the bonus is awarded, your streak resets

Permanent Penalty for Wrong Button Presses

Pressing the wrong button at any time—regardless of the round—results in a −1 point penalty
This penalty is separate and does not cancel out any positive points earned during the same round

No Negative Scores

Your score will never drop below zero, no matter how many mistakes you make
This safeguard was also part of the original version

Special Performance Song

Reach a score of 120 and unlock a unique bonus melody
With only 50 levels available, hitting this score is no easy feat—it’s a true test of mastery!

You can download the source code here.