324 Tschai's Tic-Tac-Toe
324 : Tschai's Tic-Tac-Toe
- Author: tschai-yim
- Description: The classic Tic-Tac-Toe game implemented in ASIC for maximum performance!
- GitHub repository
- Open in 3D viewer
- Clock: 0 Hz
How it works
This project is a hardware-accelerated, two-player Tic-Tac-Toe implementation. The design is optimized for high throughput and performance to meet the extreme demands of the legendary three by three board game (some might even say it's NP-complete).
Visual States:
- IDLE: A single LED sequence rotates around the 3x3 board.
- Player 1: Solid ON.
- Player 2: Slow Pulsing (50% duty cycle).
- Win: The three LEDs forming the winning line flash rapidly.
- Draw: If the board is full with no winner, the Player 2 LEDs flash rapidly (Sparkle pattern).
- Error: If an occupied cell is selected, that LED strobes rapidly for one second.
How to test
- Power On: Upon reset, the board enters
IDLEmode. You will see a single LED "rotating" around the 3x3 grid. - Start Game: Player 1 presses any of the 9 buttons. Their mark is placed immediately, and the game transitions to Player 2's turn.
- Gameplay:
- Players take turns pressing buttons to occupy empty cells.
- If you press an already-occupied cell, that cell will strobe for one second to indicate an error, and the turn remains with the current player.
- Winning: Once a line of three is formed, the game enters
GAME_OVER. The winning line will flash rapidly. - Reset: Press any button during the
GAME_OVERstate to clear the board and return to theIDLErotation animation.
External hardware
The project requires 9 momentary pushbuttons and 9 LEDs arranged in a 3x3 grid.
Pinout Mapping:
| Component | ASIC Pin(s) | Description |
|---|---|---|
| Buttons 0-7 | ui_in[7:0] |
Inputs for the first 8 cells (Top-Left to Bottom-Middle). |
| Button 8 | uio_in[0] |
Input for the 9th cell (Bottom-Right). |
| LEDs 0-7 | uo_out[7:0] |
Outputs for the first 8 LEDs. |
| LED 8 | uio_out[7] |
Output for the 9th LED. |
Wiring Requirements:
- Pull-down Resistors: Each input pin (
ui_inanduio_in[0]) should have a 10kΩ pull-down resistor to Ground. The buttons should connect the pin to VCC (3.3V) when pressed. - Current Limiting: Each LED output must have a current-limiting resistor (recommended 330Ω to 470Ω) to stay within the safe 4mA drive strength of the ASIC I/O pads.
IO
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | Button Top Left | LED Top Left | Button Bottom Right |
| 1 | Button Top Center | LED Top Center | |
| 2 | Button Top Right | LED Top Right | |
| 3 | Button Middle Left | LED Middle Left | |
| 4 | Button Middle Center | LED Middle Center | |
| 5 | Button Middle Right | LED Middle Right | |
| 6 | Button Bottom Left | LED Bottom Left | |
| 7 | Button Bottom Center | LED Bottom Center | LED Bottom Right |