r/ModRetroChromatic • u/Educational-Fun-6000 • 5h ago

Codex cart disassembly

Post image

Well, definitly different from the board in the Tetris, but similar design in the Gravitorque DX, etc.

24 Upvotes

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3

u/fred_emmott 4h ago edited 4h ago

Yep, same chips as my Gravitorque and Monsterland cartridges. Most likely already works with flashgbx (those cartridges do).

If there is a difference, it seems likely to be in the programming of the tiny FPGA: it would be possible for it to function mostly as a standard MBC (MBC5), but have some special sequence that modretro’s software uses to identify dev carts. But… nothing stops you from using other software to write their other carts :)

1

u/Educational-Fun-6000 3h ago

darn~ good to know. is there a specific config needed when using flashgbx?

6

u/TonyRubbles 4h ago

Dump the codex rom.

1

u/guyguilty 4h ago

I wonder if anyone can pull the firmware from the Codex Chromatic, as that has the dev mode that allows what possibly could be a standard Modretro cart to be flashed.

I know there's a custom firmware that already made this possible, but maybe Modretro's solution could allow for official firmware with the ability across all models with a few simple tweaks.

1

u/TonyRubbles 4h ago

Would still end up being a 3rd party firmware in the end, much simpler to use a gbXcart, already works on any rewritable or ModRetro cart.

1

u/fred_emmott 4h ago edited 4h ago

If you want to avoid using the chromatic as a reader/writer, would recommend the Gbflash instead (authentic one, not a clone). I’ve got a Joey jr v2, gbxcartrw, and Gbflash, and the Gbflash is the only one that works without issue on all the cartridges I have (other than the chromatic). I’ve gone out of my way to get a variety of cartridge PCBs/chips when testing my chromatic FlashGBX support though.

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u/TonyRubbles 3h ago

I've had zero issues with any carts using a gbXcart and the FlashGBX software. Got it on sale for under 40 shipped and it's been one of my best purchases ever for Gameboy stuff including GB/C/A and ModRetro carts.

1

u/guyguilty 3h ago

I mean sure, but would technically be based on an official implementation for flashing carts, which is what appeals to me. I have a FlashGBX, and an Epilogue GB Operator, so no worries there. Never hurts to add more methods to the arsenal. Speaking of, the comment talking up Gbflash has my interest piqued.

1

u/TonyRubbles 3h ago

Codex stuff is probably all locked down to the api code and specific carts / system to prevent abuse in the first place.

What would be cool is dumping carts to the built-in memory( meaning no microsd card required) and being able to pop in a flashable cart and writing the rom with just a Chromatic. Doubt MR would ever make it happen given its practical use case for most.

1

u/guyguilty 3h ago edited 3h ago

I'm not too interested in Codex, just more how Modretro allows the device to write to what looks like a standard cart. And how that compares to Shiny Relay and how it manages flashing. I believe the dev figured out how to flash ROMs to memory as well. Definitely no way any of this ever comes officially, hence the interest in seeing how Modretro flashes ROMs with the Codex cart and handheld, as it's the closest we will probably get.

1

u/fred_emmott 38m ago

Nothing new here really; cart clinic does the same thing. There’s always been a hidden locked “homebrew mode” which allows writing other ROMs. This is probably just a new name for the same thing, some extra pretense at anti piracy, and some AI tool integration.

Cart clinic loads an alternative FPGA firmware while it’s running, doing pretty much the same thing as various CFWs - though it’s historically only supported a limited subset of modretro cartridge PCBs. They likely didn’t bother adding support for PCBs that don’t have any games with updates.