“This simple game for the ATtiny85 is a maze that you navigate with four pushbuttons. The available paths in each direction are shown by four LEDs. A lit LED means that your way is blocked by a wall, and a speaker beeps if you try to move in that direction. When you get to the goal a tune confirms you’ve succeeded!
The project is a good example of what you can achieve with the diminuitive ATtiny85; as well as mapping the maze it’s driving four LEDs, reading four pushbuttons, and playing tones through a speaker!
The maze is designed on a 16x16 grid, and is represented in the program as an array of 16-bit numbers, with a ‘1’ bit representing a wall and a ‘0’ bit representing a passageway.”