Differences between game versions
Many games go through several revisions, usually to fix bugs. Here's a partial
listing of ROM revisions.
Defender - White, Blue, Green and Red versions
White was in the prototype games. It is a 10-chip version which did
not have a ROM test, and the RAM test was incomplete. When the game is turned
on, the top high score is "DRJ 20000".
Blue and Green do not detect all RAM bank 2 errors. Blue consists of
10 chips, while Green is 11 chips.
Red works with upright and cocktail games, and credits are retained
after power down. There are also more liberal adjustments for play difficulty.
There are 11 Red EPROMs.
Joust - Red, Yellow and Green versions
Red and Yellow have 'pterodactyl cheat'
Red has default high score of 107212, Yellow and Green are 109102
Robotron - Yellow w/ Orange stripe and Blue versions
Yellow/Orange has default difficulty of 5, demo calls Quarks 'Cubeoids', default high score is 131682
Blue has default difficulty of 3, default high score of 151782
There is also a modification to the Blue image that fixes the