Atari 7800:Game Incompatibilities

2600 Games with Issues
Although the Atari 7800 was designed to be backwards compatible with all Atari 2600 games, in actuality there are some 2600 games which will not boot or function properly on certain revisions of the 7800 hardware. Earlier consoles from the initial 1984 run and shipped during 1986 (consoles with an expansion port) seem to have the least issues, with later consoles having more problems. Listed below are some of the 2600 games which are known to have compatibility problems on later versions of the 7800.


 * All Tigervision games are incompatible with all 7800s due to the dust cover posts poking out too far, preventing the game PCB from actually making contact with the cartridge port
 * Arcadia Supercharger add-on games
 * Robot Tank
 * Space Shuttle
 * The Activision Decathlon

Many of these incompatibilities can be fixed by removing a capacitor which forms part of a timing circuit, which was added to the system's motherboard during 1987. Removing this capacitor may also break compatibility with a few other 2600 games, namely Dark Chambers and Kung-Fu Master. Both of these games in particular have (arguably superior) ports on the 7800 however.

PAL Games with Issues on NTSC 7800
Note that the BIOS on NTSC 7800 consoles must be replaced with a different one that does not perform the encryption check, otherwise no PAL games will even boot. This issue does not apply to flash carts such as the Concerto as they clear the encryption check.

Also note that most PAL games will have the screen shifted down as they were reprogrammed to take advantage of the extra resolution PAL offers over NTSC. Some games that function correctly may also have slightly different colors due to the NTSC and PAL MARIA graphics chips having different color palettes.

These games were tested on a 1984-built NTSC 7800 using a Concerto flash cart.