Hardware/Software Co-Design of a High-Speed Othello Solver

This paper presents an improved Othello game solver using the Hardware/Software Co-Design approach. Enhancements in Data Communication, Searching Algorithm, and Evaluation function have been made to beat the prevalent implementations. A novel 64-bit Communication model is proposed which transfers the current board position from the Processing System to the Programmable Logic through a 64-bit change board, instead of the complete 128-bit board. The proposal uses NegaScout searching algorithm along with Transposition Table and Node Ordering; and features like Opening Book, Killer Heuristics, and Bitboards. An Adaptive Evaluation function assigns variable weights to Mobility, Stability, Corner Occupancy, and Disc Differential depending upon the game stage. At a search depth of eight, the proposed communication model improves the communication overhead by 19.5%. Overall, the proposed design demonstrates 75.06% improved performance as compared to the prevalent implementation, and 6.53 times faster than its software implementation on the same platform.