interfaces to the controllers and console switches. System revisions Initial version: two joystick ports on lower front panel. Side expansion port for upgrades and add-ons. Bundled with two CX24 Pro-Line joysticks, AC adapter, switchbox, RCA connecting cable, and Pole Position II cartridge. Second revision: Slightly revised motherboard. Expansion port connector removed from motherboard but is still etched. Shell has indentation of where expansion port was to be. Third revision: Same as above but with only a small blemish on the shell where the expansion port was. Peripherals The Atari 7800 came bundled with the Atari Pro-Line Joystick, a two-button controller with a joystick for movement. The Pro-Line was developed for the 2600 and advertised in 1983, but delayed until Atari proceeded with the 7800. The right fire button only works as a separate fire button for certain 7800 games; otherwise, it duplicates the left fire button, allowing either button to be used for 2600 games. While physically compatible, the 7800's controllers do not work with the Sega Master System, and Sega's controllers are unable to use the 7800's two-button mode. In response to criticism over ergonomic issues with the Pro-Line controllers, Atari later released a joypad controller with the European 7800. Similar in style to controllers found on Nintendo and Sega systems, it was not available in the United States. The Atari XG-1 light gun, bundled with the Atari XEGS and also sold separately, is compatible with the 7800. Atari released five 7800 light gun games: Alien Brigade, Barnyard Blaster, Crossbow, Meltdown, and Sentinel. Cancelled peripherals After the acquisition of the Atari Consumer Division by Jack Tramiel in 1984, several expansion options for the system were cancelled: The High Score Cartridge was designed to save high scores for up to 65 separate games. The cartridge was intended as a pass-through device, similar to the later Game Genie. Nine games were programmed to support the cartridge. The expansion port, to allow for the addition of a planned computer keyboard and connection to laserdisc players and other peripherals, was removed in the second and third revisions of the 7800. A dual joystick holder was designed for Robotron: 2084 and future games like Battlezone, but not produced. Games While the system can play the over 400 games for the Atari 2600, there were only 59 official releases for the 7800. The lineup emphasized high-quality versions of games from the golden age of arcade