System 9 games have the software revision identified with an "L" to
signify the Level of software release. To see what version your game is
running, set your test switch to AUTO/UP and press ADVANCE while in Game Over
mode. You will see "2GGG" in the player 1 display, where GGG is the game
number. The player 2 display will show the number of the installed game
revision.
Sound/Speech ROMs
All Sound and Speech ROMs for the System 9 games are included with the
game ROM file. Not all games use all chips, and the chip size varies per game.