HOW TO – Arduino Tilt Game “Mosfet’s Roundup”

I wanted to see if the accelerometer breakout board could be used to make a game controlled by tilting. The result is a game where you help Mosfet the cat round up bouncing Adafruit logos.

For this project I used:

The OLED is connected to the Arduino by following the wiring in the tutorial. The tilt sensor provides values in the range of 0 to 3.3v, but the Arduino expects values in the range of 0 to 5v. Looking through the Arduino documentation, the analogueReference function allows you to specify how the Arduino determines the top of the input range for analogue sensor reads. Passing the EXTERNAL option to it and connecting the 3.3v out pin on the ADXL335 breakout board to the AREF pin on the Arduino sets the top to 3.3v. In the end, I found that I didn’t need to worry about the range to this level for simple tilt sensing, but liked the idea of having the input ranges match.

The accelerometer is added to the circuit as below:


Arduino Uno image courtesy of Fritzing

In the code, the X and Y values from the sensor are flipped to match the OLED’s X and Y coordinates. Additionally, the sensor values are captured at startup to use as a reference point for “level” to determine the tilt of later reads:

 // Assume the sensor is level, capture the current values as origin
 origin_y = analogRead(X_IN_PIN);
 origin_x = analogRead(Y_IN_PIN);

I found that the raw sensor reads were too sensitive for gameplay to be predictable. I handled this by dividing the change value by 10:

  // Read the sensor values and swap coordinates to match OLED.
  raw_sensor_x = analogRead(Y_IN_PIN);
  raw_sensor_y = analogRead(X_IN_PIN);

  // Center sensor reads on origin and reduce jitter.
  tilt_sensor_x = (raw_sensor_x - origin_x) / 10;
  tilt_sensor_y = (raw_sensor_y - origin_y) / 10;

Full source is available on github.  I hope you enjoy playing Mosfet’s Roundup and I’d love to see what you’ve done with the tilt sensor.


Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here: adafruit.com/editorialstandards

Join Adafruit on Mastodon

Adafruit is on Mastodon, join in! adafruit.com/mastodon

Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.

Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7pm ET! To join, head over to YouTube and check out the show’s live chat – we’ll post the link there.

Join us every Wednesday night at 8pm ET for Ask an Engineer!

Join over 36,000+ makers on Adafruit’s Discord channels and be part of the community! http://adafru.it/discord

CircuitPython – The easiest way to program microcontrollers – CircuitPython.org


Maker Business — “Packaging” chips in the US

Wearables — Enclosures help fight body humidity in costumes

Electronics — Transformers: More than meets the eye!

Python for Microcontrollers — Python on Microcontrollers Newsletter: Silicon Labs introduces CircuitPython support, and more! #CircuitPython #Python #micropython @ThePSF @Raspberry_Pi

Adafruit IoT Monthly — Guardian Robot, Weather-wise Umbrella Stand, and more!

Microsoft MakeCode — MakeCode Thank You!

EYE on NPI — Maxim’s Himalaya uSLIC Step-Down Power Module #EyeOnNPI @maximintegrated @digikey

New Products – Adafruit Industries – Makers, hackers, artists, designers and engineers! — #NewProds 7/19/23 Feat. Adafruit Matrix Portal S3 CircuitPython Powered Internet Display!

Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !



1 Comment

  1. Similar game project, from several years ago:

    http://www.saccade.com/writing/projects/NecTilt/Tilt.html

Sorry, the comment form is closed at this time.