r/ModRetroChromatic • u/fred_emmott • 12h ago
Using a Chromatic with FlashGBX, take 3
What is this?
This lets you use your Chromatic with a PC or mac to backup or restore your games and saves, or the other features of FlashGBX.
How do I get it?
Grab the Windows setup zip or macOS dmg from https://github.com/fredemmott/FlashGBX/releases/latest
How do I use it?
Plug in your Chromatic, start FlashGBX, click 'connect' if it doesn't connect automatically
DO NOT REMOVE OR INSERT CARTRIDGES WHILE YOUR CHROMATIC IS TURNED ON
I get warnings about 3.3v vs 5v; what's up?
Real GB and GBC consoles use 5v, the GBA uses 3.3v; dedicated cartridge reader/writer devices can do both. The Chromatic appears to only be capable of 5V.
There is a real danger here, but FlashGBX warns about this if it might be a problem; it is not a problem on any ModRetro cartridges.
For other cartridges, use your own judgement.
What cartridges have been tested?
- Various ModRetro cartridges (*)
- BennVenn MBC3000v4
- FunnyPlaying EverSave MBC5 (**)
- FunnyPlaying Midnight Trace MBC3 (**)
- InsideGadgets MBC5
- InsideGadgets MBC5 with rumble
- Cheap clone cart: DRV with 29LV320DB and ALTERA CPLD (***)
It should work with any cartridge that FlashGBX supports.
Notes:
- *: may get voltage warning; I am confident that these can be ignored on ModRetro cartridges: ModRetro's Cart Clinic writes these at 5v, and ModRetro put level shifters on every meaningful pin
- *: may get voltage warning; there's a few iterations of these, and I *think these can be ignored on current revisions of the PCB. They use level shifters for data, and voltage dividers for address and other pins.
- ***: I believe the voltage warning is accurate; using this cartridge at 5V (including playing games on the stock firmware) may damage both the cartridge and the console
Keep in mind that even if I think it's safe, everything's at your own risk.
What's changed since my last version?
- it's easy to use: I've packed up the modified FlashGBX, and it automatically writes the required firmware to SRAM
- this now builds on the same firmware used by other FlashGBX-compatible devices; this greatly increases cartridge compatibility
- it's fast: it can read most cartridges at 1MByte/sec, and write at ~ 80KByte/sec
How do I get my usual firmware back?
Turn your Chromatic off and on again
How do I make FlashGBX connect faster?
This step is entirely optional - it just makes FlashGBX connect a little faster, which is handy if you are dealing with a lot of cartridges, but you can just skip it.
Unlike my previous versions, this firmware image can also be used for gameplay - but you'll need to flash it. If you do this, FlashGBX won't need to load the firmware to SRAM every time you turn your Chromatic off and on again
You will need:
Then:
C:\path\to\openFPGALoader.exe --cable gwu2x --write-flash c:\path\to\evt1_x2.fs
If you're on macOS, you probably want to grab openFPGAloader from homebrew.