I have noticed that several Game Boy games contain a 32-byte footer at the end of one or more 16KB banks. For example, in "Kirby's Pinball Land (USA, Europe)" and "Kirby no Pinball (Japan)":
Very similar footers exist in "Kirby's Dream Land", and footers in the same format exist in other games, including:
Another thing these games have in common is that they all seem to use the same pattern to fill blank space - 32 bytes of $00 alternating with 32 bytes of $ff. In some cases this filler contains a significant number of flipped bits.
Does anyone know whether these 32-byte footers have any meaning? The values do not seem to be dependent on the contents of the 16KB bank - note that the two releases of "Kirby's Pinball Land" contain exactly the same footers, even for banks which differ.
Have bank footers similar to these been seen anywhere else? What might be their purpose?
Code:
07fe0: .. C6 01 .. 05 00 .. C1 80 .. C3 F3 .. 8A E8 .. 08 98 .. 11 10 .. 62 00
0ffe0: .. 0F 01 .. 8D 00 .. C5 13 .. 86 C0 .. 90 AD .. 23 81 .. 98 F3 .. 20 00
23fe0: .. 6E BF .. 7F DF .. FF BE .. F7 CF .. 07 DB .. 2C ED .. FF F8 .. BB 00
2bfe0: .. 66 F7 .. 5F DF .. 7F F7 .. AD DE .. EB 3D .. F3 23 .. 7F 7D .. 3F 00
2ffe0: .. 08 40 .. 40 A4 .. 15 49 .. 15 36 .. 50 8F .. 6B 0C .. F0 4D .. 10 00
3ffe0: .. 98 85 .. 21 09 .. 41 33 .. 83 48 .. F8 51 .. 33 22 .. 90 74 .. 14 00
(.. represents a pair of "blank" bytes - either $00 $00 or $ff $ff)0ffe0: .. 0F 01 .. 8D 00 .. C5 13 .. 86 C0 .. 90 AD .. 23 81 .. 98 F3 .. 20 00
23fe0: .. 6E BF .. 7F DF .. FF BE .. F7 CF .. 07 DB .. 2C ED .. FF F8 .. BB 00
2bfe0: .. 66 F7 .. 5F DF .. 7F F7 .. AD DE .. EB 3D .. F3 23 .. 7F 7D .. 3F 00
2ffe0: .. 08 40 .. 40 A4 .. 15 49 .. 15 36 .. 50 8F .. 6B 0C .. F0 4D .. 10 00
3ffe0: .. 98 85 .. 21 09 .. 41 33 .. 83 48 .. F8 51 .. 33 22 .. 90 74 .. 14 00
Very similar footers exist in "Kirby's Dream Land", and footers in the same format exist in other games, including:
- Adventures of Star Saver, The (USA, Europe)
- Alien vs Predator - The Last of His Clan (USA)
- Bonk's Adventure (USA)
- Desert Strike - Return to the Gulf (USA)
- Jetsons, The - Robot Panic (USA, Europe)
- Jurassic Park (USA)
- Mysterium (USA)
- Pac-Attack (USA)
- Snow Bros. Jr. (USA)
- Spud's Adventure (USA)
- Top Gun - Guts & Glory (USA, Europe)
Another thing these games have in common is that they all seem to use the same pattern to fill blank space - 32 bytes of $00 alternating with 32 bytes of $ff. In some cases this filler contains a significant number of flipped bits.
Does anyone know whether these 32-byte footers have any meaning? The values do not seem to be dependent on the contents of the 16KB bank - note that the two releases of "Kirby's Pinball Land" contain exactly the same footers, even for banks which differ.
Have bank footers similar to these been seen anywhere else? What might be their purpose?