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Pokémon Yellow predefined functions list

This is a list of
  • REDIRECT Template:Yellow predefined functions. All values are in hexadecimal.

    Some values that are stated "Nonfunctional" and "Softlock" may do something when certain conditions are met.

    Executing predefined functions

    Hacked ROM

    Predefined functions can be executed with TheZZAZZGlitch's debug Pokémon Yellow by using the "Debug" item (known as "31337" in earlier ROMs), which can be withdrawn from the player's PC at the beginning of the game or added as item 1 with the GameShark code 012C1DD3.

    In at least the latest revision, one must use the debug item, select "Miscellaneous", scroll down to "Predef [7 heal]", adjust the value with right (ID +01h) and/or left (ID+10h) and press A to run the predefined function.

    List of predefined functions

    00: Shows in-battle HUD for exactly 5 frames

    01 - 03: Nonfunctional

    04: Writes random garbage to tile graphics. Effect is cosmetic.

    05 - 06: Nonfunctional

    07: Instant Pokemon Center (no animation, but HP and PP refilled and status restored to normal)

    08: Nonfunctional

    09: Softlock

    0A: Softlock

    0B - 0C: Nonfunctional

    0D - 0E: Softlock

    0F: Initialises Player Data (Party, items, badges only)

    10 - 17: Nonfunctional

    18: Initialises Player Data

    19 - 1A: Nonfunctional

    1B: First PKMN learns move named , but doesn't actually work

    1C - 1E: Nonfunctional

    1F: Poison screen flash, no sound effect or health decrease

    20: Disables Up and Down button input, menus included. (Curious.)

    21: Vertical screen shake

    22 - 23: Nonfunctional

    24: Horizontal screen shake

    25: Softlock

    26 - 28: Nonfunctional

    29: Pokedex menu

    2A: Nonfunctional

    2B: Saves the game to SRAM0

    2C: Battle start, works

    2D: Nonfunctional

    2E: Draws the 8 badges on the Trainer menu for 5 frames (uses the tileset of the loaded map)

    2F: Trade, nonfunctional

    30: Plays the battle transition

    31: Small amounts of tile corruption, text to be specific.

    32: Plays the Intro. Returns to the overworld when finished, but does not reload graphics. Any NPCs onscreen will show on-screen during intro.

    33: Nonfunctional

    34: Flashes the screen indefinitely.

    35: Nonfunctional

    36: First page of first pokemon's stats

    37: Second page of first pokemon's stats

    38: Functional trade

    39 - 3A: Nonfunctional

    3B: All tiles and sound filled with garbage.

    3C: Cut, working

    3D: Pokedex data... of Hitmonchan.

    3E: Nonfunctional

    3F: Working save

    40: Hangs for exactly 15 frames

    41 - 45: Nonfunctional

    46: Softlock

    47: Nonfunctional

    48: Softlock

    49: Heals opponent in battle, outside of battle HUD replaced with text

    4A: Hitmonchan's Nest page

    4B: Nonfunctional

    4C: Displays Emotion Bubble. Replaces text tiles 2, 3, 4, and 5 with "Trainer spotted you!" bubble.

    4D: Nonfunctional

    4E: "Nickname?" for Hitmonchan

    4F: Softlock

    50: Saves to SRAM2

    51: Nonfunctional

    52: Goes to a white screen and forcibly loads the save file, gives "file data is destroyed!" message if one does not exist. Pokemon and item data is loaded correctly however the tileset for the map is not changed if the save was in a different map.

    53: Saves to SRAM1

    54: "Wanna trade CLEFAIRY for MR.MIME?"

    55: Enter Hall of Fame, then credits. Works, but then dumps you back into whatever state you were in before calling. Does not reload graphics.

    56: Professor Oak's Rating

    57: Softlock

    58 - 5A: Nonfunctional

    5B: First item used Strength, functional

    5C - 60: Nonfunctional

    61: Elevator menu with invalid floors. The menu may display mart items. If inside an Elevator after selecting an option, the elevator will move after exiting the menu but you will exit to a glitched map.

    62: If you caught 0 kinds of pokemon, get item 0x00.

    63 - 81: Softlock

    82: Nonfunctional

    83 - 8C: Softlock

    8D: Small screen corruption, then softlock

    8E - 8F: Softlock

    90: Nonfunctional

    91: Softlock

    92: Text Box full of "BLUE" and whitespace

    93: Screen fills with second tile of "GYM" and crash.

    94: Nonfunctional

    95 - 98: Softlock

    99: Nonfunctional

    9A - 9F: Softlock

    A0: Nonfunctional

    A1: Softlock

    A2: "[]5 error." where [] = tile 25

    A3 - A5: Softlock

    A6: Nonfunctional

    A7: Text box similar to 92 but filled with "LAPRAS" instead of "BLUE".

    A8: Nonfunctional

    A9: Softlock

    AA: Nonfunctional

    AB: Battle HUD appears, then "It's not very effective..." appears

    AC: See 92

    AD: Softlock

    AE: Nonfunctional

    AF: 3TRAINERPOKe (that always turns into a Rhydon, not due to the Rhydon trap) was caught!

    B0: Text scramble, then crash

    B1 - B5: Softlock

    B6: Pops all text boxes

    B7 - FF: Softlock/Nonfunctional