A threat-based Connect6 implementation on FPGA

Connect6 is a new generation k-in-a-row game, which has drawn great interest not only from game enthusiasts, but also from researchers, due to its characteristics such as fairness and high state-space complexity. In this paper we describe the design and implementation of an FPGA-based Connect6 player that can compete against other computer-based opponents, communicating through a serial interface. Our algorithmic implementation utilises only basic FPGA building blocks such as LUTs and flip-flops and does not include any IP cores or hardware macros, making it portable across different FPGA platforms without design modifications. The design has been implemented and validated both on a Xilinx Spartan-3A, and a Xilinx Spartan-6 FPGA boards. The algorithm uses a powerful threat-based placement strategy that maximises the FPGA's winning opportunity while reducing the opponent's options. Extended simulation and evaluation based on software and human players confirms that our FPGA-based implementation performs well, and the algorithm used in the design leads to a high probability of success.