Tic-Tac-Toe

Four cool Tic-Tac-Toe variants in one device.

info

Author: Cîrstescu Andrei-Vlad
GitHub Project Link: https://github.com/UPB-PMRust-Students/proiect-cirstescuandrei

Description

This project implements a classic Tic-Tac-Toe game on an RP2350 development board, using a 2.2" SPI TFT display for
graphical output and a 4x4 button matrix for user input. Players interact with the game by selecting grid positions
via the button matrix, while the display shows the game board, moves, and results in real time. The project will also
include multiple variants to the Tic-Tac-Toe game:

• Misère Tic-Tac-Toe -> The goal is to not get 3 in a row.
• Wild Tic-Tac-Toe -> Players can place either O or X.
• Forgetful Tic-Tac-Toe -> Fourth-last moves are erased at each step.

Motivation

This project was created to explore how simple games like Tic-Tac-Toe can be made more engaging through creative
variants, while also providing a fun way to apply embedded programming skills and hardware integration. I decided upon
this project because I was interested in working with a display in an embedded context, while also recreating a staple
pen-and-paper game turned digital like Tic-Tac-Toe.

Architecture

• Raspberry Pi Pico 2 W

  • Central Microcontroller, manages button inputs and interfaces with the Display.
  • Connects directly to the Button Matrix and the TFT Display.

• 2.2" TFT SPI LCD Display(ILI9341)

  • Display to show the state of the game, as well as player scores and the game variant.
  • Interfaces with the Microcontroller through SPI.

• 4x4 Button Matrix

  • Handles inputs for X and O placements, game variant selection and restart.

• Passive Buzzer

  • Used to play the background song.
  • The song is Lost Woods(Saira's Song) from The Legend of Zelda: Ocarina of Time.

• LEDs

  • Two LEDs, green and red.
  • Lights up according to winner.

Device pictures

Log

Week 5 - 11 May

• Bought components.
• Tested button matrix and screen.

Week 12 - 18 May

• Decided to add LEDs and a buzzer.
• Finished hardware assembly.

Week 19 - 25 May

• Finished documentation.
• Translated the sheet music for Lost Woods to note frequecies and durations.
• Spent the week writing the code for the device.
• Ironed out all the bugs by the end of the week.

Hardware

• Raspberry Pi Pico 2 W

  • Connected through GPIOs to the Display and Button Batrix.

• 2.2" TFT SPI LCD Display(ILI9341)

  • SCK, MOSI, MISO, RESET, DC and CS pins connected to Pico GPIOs on SPI1.
  • LED and VCC are connected to 3V3.
  • Connections on GP2, GP3, GP4, GP5

• 4x4 Button Matrix

  • Connected to 4 input and 4 output pins on the Pico.
  • GP20, GP21, GP22, GP26 for inputs.
  • GP16, GP17, GP18, GP19 for outputs.

• Passive Buzzer

  • Connected to GP5 on the Pico.

• LEDs

  • Red LED connected to GP9.
  • Red LED connected to GP8.

Schematics

Bill of Materials

Device	Usage	Price
Raspberry Pi Pico 2 W	The microcontroller	39.66 RON
4x4 Button Matrix	Button Matrix	4.19 RON
2.2" TFT SPI Display	LCD Display	59.99 RON
Passive Buzzer	Passive Buzzer	0.99 RON
Red LED	Red LED	0.39 RON
Green LED	Green LED	0.39 RON

Software

Library	Description	Usage
embassy-rp	Framework for embedded devices	Used for general functions
embedded-hal	HAL for peripherals	Used for connecting with the buttons/display
mipidsi	Generic library for TFT displays	Used for interfacing with the display
ili9341	Display driver ILI9341	Used for the display for the Pico Explorer Base
embedded-graphics	2D graphics library	Used for drawing on the display

Links

1. Link to short demo
2. Link to the sheet music for Lost Woods from Ocarina of Time ...