yabause/bios.bin (optional): bios file of saturn
   |   /yabause.xml (auto): setting file
   | 
   |--carts/actionreplay.bin (optional)
   |       /bkram4M.bin (auto)
   |       /bkram8M.bin (auto)
   |       /bkram16M.bin (auto)
   |       /bkram32M.bin (auto)
   |       /ROM16M.bin  (optional)
   |
   |--saves/bkram.bin (auto, one-backup mode): one internal back-up file
   |       /[gameID].bin (auto, each-backup mode): internal back-up file in each game
   |       /[gameID]_00?.yss (auto): state save file in each game
