Pokémon data structure (Generation IV)

Pokémon in the games Diamond and Pearl are all stored the same way in a 136-byte structure.

• Need to figure out how checksum is computed

• Need to figure out the encryption algorithm for bytes 08-87

The Pokemon data structure is divided into four 32-byte blocks, A through D. The personality value and checksum are stored into the save data, and the remaining 128 bytes are encrypted in a never-before-seen complex method using some combination of the PV and checksum as the encryption key. (It is no longer as simple as XOR'ing the 2 values.) The algorithm needs to be figured out.

Unencrypted bytes

• 00-03 Personality value
• 04-05 Unknown
• 06-07 Checksum

Block A

• 08-09 Species ID
• 0A-0B Held Item
• 0C-0D OT ID
• 0E-0F OT Secret ID
• 10-13 Experience points
• 14 Friendship/Egg Steps to Hatch
• 15 Ability
• 16 Markings
• 17 Country of Origin
• 18-1D Effort values
• 1E-23 Contest stats
• 24-27 Ribbons

Block B

• 28-2F Moveset
• 30-33 Move PP
• 34-37 Move PP Ups
• 38-3B Individual values
• 3C-3F Unknown
• 40 Gender
• 41-47 Unknown

Block C

• 48-5D Nickname
• 5E Unknown
• 5F Hometown
• 60-62 Contests
• 63-67 Unknown

Block D

• 68-77 OT Name
• 78-7A Date Egg Received
• 7B-7D Date Met
• 7E-7F Egg Location
• 80-81 Met At Location
• 82 Unknown
• 83 PokeBall
• 84 Met At Level
• 85-87 Unknown