The author built a physical 17x17 matrix of switches with integrated LEDs to simulate Conway's Game of Life, using a microcontroller (AVR128DA64) to control rows and columns.
The LED display uses a multiplexing scheme where each row is active for 1/17th of the time, requiring higher current (150 mA per LED) to maintain brightness, with MOSFETs for row and column switching.
User input is detected by reusing row select lines to ground and sensing switch closures via GPIO pins, with pull-up resistors integrated on the MCU.