294 Tiny Rainbow Snake Game
294 : Tiny Rainbow Snake Game
- Author: Lilly Das
- Description: The snake game you know and love, but tiny and rainbow.
- GitHub repository
- Open in 3D viewer
- Clock: 25000000 Hz
How it works
This project is a SV implementation of the Snake game, except the maximum snake size is capped at 20 to fit the 1x2 tile limit, and the snake is rainbow for fun. The game is displayed via a VGA interface (640x480 resolution) and the gameboard is 8x8 tiles centered centered in the middle of the screen. Each game tile is 32x32 pixels so the gameboard is 256x256 pixels.
The snake is implemented as a 20-tile shift register storing each tile of the current snake's row/col. This shift register takes up the majority of the tile space hence the cap at length=20. But, you can still keep playing the game after the maximum snake size is reached, the snake just won't grow anymore. You'll see the displayed scores turn purple when the max size is reached and they can keep incrementing till score=99 since I only put enough space for 2 BCD digits. If you're a total beast at snake game and reach 99 points, the score will just hold there as I didn't have the space for a special endgame visual.
How to test
- Hook up a 25MHz clock to the chip (since the VGA is running at 640x480 resolution - technically should be 25.175MHz pixel clock but 25MHz has been working just fine for me).
- Hook up rst_n to a button or something else that you can easily pulse.
- Hook up buttons or joystick to the ui_in[4:1] input pins. ui_in[4] = RIGHT, ui_in[3] = LEFT, ui_in[2] = DOWN, ui_in[1] = UP.
- Also hook up a button to ui_in[0] for the start_game control input.
- Connect R0, R1, G0, G1, B0, B1 (6-bit RGB) and VGA_HS, VGA_VS pins to TinyVGA PMOD board, and connect that PMOD to a VGA monitor. {VGA_HS, B0, G0, R0, VGA_VS, B1, G1, R1} connect to uo_out[7:0], as per the recommended TT VGA pinout.
- You can also connect the output LEDs if you want, but this is optional as the LED outputs are just showing the current button presses. These will be on the bidirectional I/O pins, uio[7:0].
- Hopefully you should be able to play now!
External hardware
- 6x buttons, or 2x buttons if using joystick for move controls
- Joystick if desired
- VGA monitor + VGA cable
- TinyVGA PMOD connector (I only have 6-bit RGB)
- 4x LEDs if desired
IO
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | START_GAME_BTN | R1 | LED0 |
| 1 | UP_BTN | G1 | LED1 |
| 2 | DOWN_BTN | B1 | LED2 |
| 3 | LEFT_BTN | VGA_VS | LED3 |
| 4 | RIGHT_BTN | R0 | LED4 |
| 5 | G0 | LED5 | |
| 6 | B0 | LED6 | |
| 7 | VGA_HS | VGA_BLANK |