gb-save-states

Patches to add save state support to Game Boy and Game Boy Color games when playing on the original hardware.

How to use

Requirements

• For Game Boy games:

  • Flash cart that supports 32KB of save RAM and MBC 1/5 mapper

• For Game Boy Color games, and Game Boy games that originally include save RAM:

  • Flash cart that supports 128KB of save RAM and MBC 5 mapper, e.g. EZ Flash Jr. or EverDrive-GB X3/X5/X7. Not sure how much save RAM your flash cart supports? Try this test ROM on your flash cart.

• Original ROM file for the game

• Patching software that supports bsdiff patches:

  • Windows (command line) - BsPatch
  • macOS (GUI) - Multi Patch
  • macOS (terminal) - install Homebrew and then run brew install bsdiff in the terminal

Setup

1. Download the .bsdiff patch file for the game from the patches directory

2. Patch your original ROM with the patch to build a new patched ROM.

   Example for command line/terminal:

   bspatch "B.C. Kid (E) [!].gb" patched.gb "B.C. Kid (E) [!].gb.bsdiff"
   

3. Copy the patched ROM to your flash cartridge

Controls

Due to different button layouts on the GB/GBC and the GBA, there are two different button combinations that can be used to save/load a game.

After pressing the button combo, the screen will flash as the save/load process runs.

Save

Combo 1: Hold Down and press Start

Combo 2: Hold Select and press A

Load

Combo 1: Hold Up and press Start

Combo 2: Hold Select and press B

There isn't a patch for my favourite game!

Submit an issue and hopefully someone will create a patch for you.

If you have a bit of Game Boy assembly knowledge then you can create a patch yourself. Check out the How To document

Limitations

• Sound/Music cannot always be restored 100% due to some sound registers being read only. This generally isn't a problem unless loading a save game from the startup menu instead of during gameplay. Pausing and resuming the game can sometimes resolve any sound problems.

Notes

• Kirby's Dream Land uses Select + Down + B and Select + Up + A to access hidden features on the title screen. To avoid conflicts with the save/load combos, these hidden feature combos have been remapped to Down + B and Up + A.