GridPix EasyFlash

This is the source of a tool that creates a C64 EasyFlash cartridge from the GMod2 cartridge of the GridPix game.

How to patch your GMod2 cartridge

1. Purchase a copy of the game from itch.io
2. Download GridPix.zip and extract the contents
3. Download the latest Xdelta3 patch file from this repository
4. Navigate to https://www.marcrobledo.com/RomPatcher.js/
5. For the ROM file select the gridpix.crt file extracted from GridPix.zip
6. For the Patch file select the gridpix_easyflash_patch.xdelta file downloaded from here
7. Click Apply patch, your browser will automatically download gridpix (patched).crt

You can use the resulting file with an emulator or flash it to a physical EasyFlash cartridge.

How to build the patch

You can also build the cartridge and patch files yourself using the code contained in this repository.

You need the following tools. I cannot be sure about the minimal version requirements, I put the versions I used in brackets:

• GNU Make (3.81)
• Rust (1.91.0)
• ACME Assembler (0.97)
• Xdelta (3.1.0)

Make sure that you have all the listed tools installed. Then, copy the original gridpix.crt to the in directory. Finally, execute make.

This will create these files in the out directory:

• gridpix_easyflash.crt (the EasyFlash cartridge)
• gridpix_easyflash_patch.xdelta (the Xdelta3 patch file that converts the GMod2 cartridge to EasyFlash)

License and Copyright

The code is © 2023 Malte Thiesen, available under the MIT license.

The patch code is based in part on code by Luigi Di Fraia, also available under the MIT license.

The original GridPix game is © 2020 Thalamus Digital Publishing Ltd. No copy of the original game is included in this repository.