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 has 11.
- 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 ROMs. (ROM 5 is not
Joust - Red, Yellow and Green versions
- Red and Yellow have the '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 ROM image that fixes the 'shot-in-the-corner