Gaming What kind of witchcraft is this?

[bladerx]

Reading the listing, it seems to just be the GBC games on a GBA cart, but unless they are running on a GBC emulator for GBA, I don't know how they could be run on a DS.

http://www.ebay.com/itm/Legend-of-Z...hash=item4b1f6249f0:m:mh-HFklkc4AyMVBqHnT6EAw

 

[The Catboy]

I found this
https://www.etsy.com/listing/473296243/legend-of-zelda-oracle-of-ages-gba
My only guess is most likely they stripped down the GBC game and injected a custom ROM into the chip, but that's just a guess.
I do know however, that the case they used are Pokemon Ruby and Sapphire's cases.

 

[DinohScene]

ROM hack on a custom PCB, likely.

 

[Issac]

Huh... that's interesting. I wonder how it's made to work on the DS and stuff. Maybe some auto-run emulator.

 

[tech3475]

Likely just the ROM running in an emulator.

I'd be surprised if the carts were real though, at least in terms of the battery.

 

[MHDestination]

Those are fake cartridges.

You can get them on Aliexpress for 5 bucks.
https://www.aliexpress.com/item/Nin...-of-Seasons-English-Language/32793734305.html

I guess they convert the gbc roms to gba using goomba emulator.


EDIT: 20 $ for a fake cart ??? That's highly criminal and should be reported.

 

[Localhorst86]

I am a curious guy. I decided to buy both games (Oracle of Seasons and Oracle of Ages) because I figured they are less than 5 bucks each. Might be a cool novelty.

Hardware
The cartridges arrived today and they look very good. The labels are finished in a glossy print that looks very detailed to me but not as good as an original GBA label. The cartridges themselves feel very solid, there are no gaps, sharp edges or protrusions, nothing is rattling inside. I can see a battery inside both of those cartridges so they are most likely SRAM based. One thing I noticed is that the cartridges stick out about 1mm further than original GBA carts - nothing you'd really notice just casually looking at it but definately noticable when you move your finger across the top of the GBA.

Software
The games are, as expected, just GBC roms running in an emulator (Goomba Color 12-14-14 to be exact). Not exactly a surprise, I was hoping they had found a more sophisticated way to get them on a GBA, though. Because of the way they are made, they should be running on anything that runs GBA cartridges. I have personally tested them on a GBA, GBA SP, DS Lite, Gameboy micro, Revo K101+ (GBA clone) and a gamebox (another GBA clone) and all worked fine. The usual Goomba Color limitations apply, i.e. you can not run the game in full screen and as far as I know you can not link these games up. The ROMs used are the US release of the games therefore there is no way to change the language to french or german.

If you want these games you are probably better off getting the GBC originals (or reproductions if you like) over these, unless you do not have any Hardware that plays GBC games or a native GBC emulator.

All in all the 10 bucks i spent on these didn't put me on the streets and it's sorta funny to have them. I am not going to buy any other "GBA Edition" games, though.

 

[Mikemk]

@Localhorst86 would you please dump the roms and see if they've been modified from the official releases?

 

[Localhorst86]

I dumped the ROMs. The cartridges seem to be 128Mbit cartridges, the Original GBC titles were only 8Mbit. I stripped the Goomba emulator from the roms and trimmed the exceeding ~120Mbit of blank data (FFs) and compared them to the US versions of the games (CRC 3800a387 for OoA, CRC d7e9f5d7 for OoS). For both games there were only 7 bytes different, not sure if that was caused by putting it through Goomba. Here you can find the two IPS patches to make the aforementioned dumps from the no-intro set into the dumps from these cartridges.

For some reason the original cartridges jump to 0x150 after the nintendo logo whereas the GBA titles seem to jump to 0x30 which seemingly contains an instruction to jump to 0x150 - not sure what this extra jump is for.

 

[Mikemk]

Could be to trick it into loading the GBA shop, requires a processor flag to be set. I'm not familiar enough with 20 year old ARM assembly to know the side effects branching has.

Does Goomba set the GBA flag when booting the virtual GBC?

 

[Localhorst86]

Could be to trick it into loading the GBA shop, requires a processor flag to be set. I'm not familiar enough with 20 year old ARM assembly to know the side effects branching has.

Does Goomba set the GBA flag when booting the virtual GBC?

Goomba has a menu option to identify as GBA. There should not be a need to modify the rom

 

[GreatCrippler]

Goomba GBA. Not complicated

 

[Localhorst86]

Took one of these appart, just if anyone is interested.

 

[Localhorst86]

Could be to trick it into loading the GBA shop, requires a processor flag to be set.

Guess what, it actually is. Running the original and modified ROM side by side we can see that the game is allowing access to the GBA store as well as using a lighter "washed out" color palette for the GBA as was common in the time due to the GBAs unlit screen. Here's a side by side comparison, left is the unaltered US ROM, on the right we have the ROM from the "GBA Edition" cartridge.
Kinda weird seeing as Goomba would have such an option built in.
https://i.imgur.com/LDT1XKf.png