Since when did Tennis need wires?
Wireless Tennis is a Plug & Play Tennis game running on SunPlus SPG240 hardware. It appears to be a clone of Epoch's Excite Tennis Plug & Play game.
Test Menu#
Booting the game while holding A + B + Down will redirect the player to a test menu. After all tests are complete, the player will be redirected to an input test screen, which can be exited by holding A + B + Up.
(Source: David Haywood)