Is it possible to use an R4 flash cart to use AR codes on an unofficial GBA cart?

[Weltock]

I have this green "Mega Man Battle Network Collection" GBA cart that has all 12 games of that series, specifically the Wii U virtual console versions of those games ported onto it. (I can't seem to post my photo of it.)

One of those games, Mega Man Battle Network 6, had a nasty soft-lock situation in the Japanese version, which returned in the English translation of that version for the virtual console. I got stuck in that soft-lock.

Now, somebody made an AR code exactly to solve this situation. But my GBA Action Replay doesn't work at all. So, if possible, I'd like to use that AR code with an R4 to send the cheat code to the GBA cart in a DS Lite --- if that's something a flash cart can do.

But will it work on a cart that is not one single game, but several? I've never used a code on this kind of conglomerate game before, and I don't want to screw something up.

Thank!

 

[FAST6191]

DS mode launching GBA mode is possible but you don't retain any memory even if you could somehow force a jump to it to act as a cheat engine. To that end nothing like the GBA equivalent of http://www.chishm.com/NitroHax/index.html if that is where you were heading.

Your options then become dumping the saves which can be tricky with those multi carts -- GBA carts top out at 32 megabytes which the first 3 games would take up, maybe one more if the trimming works in your favour, and thus something fun will need to be done to handle things. I don't know what they would have done here either -- most pirate multi carts for the GBA are either repurposed flash carts (doubtful here if it is all the games and revisions plus a menu) or rather more basic affairs (several takes seen over the years, https://gbatemp.net/threads/sram-bank-switching-on-bootleg-cartridges.547662/ being a twist beyond standard protocols). 12 games even without 4.5's 512K Flash would also put it above the 2Mbit that baseline cartridges top out at so not sure what is being used to pull that off.
Said trickiness is also why your AR does not work either, same as https://doc.kodewerx.org/hacking_gba.html#nonstandard .

If it is a repurposed flash cart and you can figure out how to write it then you might be able to hardpatch the cheat in with something like https://gbatemp.net/threads/gbaatm-rebirth-gba-auto-trainer-maker-a-new-hope.564321/ but that is getting a bit radical at that point.

I have not looked up what the softlock is here either (I knew the one for 4 on the DS https://www.nintendo.com/consumer/systems/gameboy/trouble_specificgame.jsp but these I am less familiar with) but depending upon the nature of the softlock if reverting to an earlier save might cure it/allow a dodge then you might be able to force that if the game uses alternating save banks by turning off during saving but that risks everything.

If you or someone you know has one of those nice analogue pocket devices then you could actually snatch a savestate from that, edit the savestate (AR codes are just instructions on editing memory addresses, which you have the complete ones for by dint of having the codes) and restore that (I did something similar in https://gbatemp.net/review/analogue-pocket-gb-gbc-and-gba-handheld-fpga-based-player.2081/ ). It would probably have to be a device of that potency as well -- the more classical dumper-emulator combo that most historical clones are will probably only get the menu you use to select the games.
I don't know what goes for hacked GB players these days but I could see a path there https://github.com/FIX94/gba-link-cable-dumper/releases for a jumping off point, though it would take more work and basically be a custom dumper.

Re photos. If you can post one of the PCB (even on an external site and break up the url a la www . somesite . tld / blahnumbers , or say whatever image host and the unique bits so we can reconstruct it) I and probably several others would be interested; what you describe is a step above what we normally see for bootleg/pirate/repro carts, and indeed several vintage flash carts.

 

[Weltock]

DS mode launching GBA mode is possible but you don't retain any memory even if you could somehow force a jump to it to act as a cheat engine. To that end nothing like the GBA equivalent of http://www.chishm.com/NitroHax/index.html if that is where you were heading.

Your options then become dumping the saves which can be tricky with those multi carts -- GBA carts top out at 32 megabytes which the first 3 games would take up, maybe one more if the trimming works in your favour, and thus something fun will need to be done to handle things. I don't know what they would have done here either -- most pirate multi carts for the GBA are either repurposed flash carts (doubtful here if it is all the games and revisions plus a menu) or rather more basic affairs (several takes seen over the years, https://gbatemp.net/threads/sram-bank-switching-on-bootleg-cartridges.547662/ being a twist beyond standard protocols). 12 games even without 4.5's 512K Flash would also put it above the 2Mbit that baseline cartridges top out at so not sure what is being used to pull that off.
Said trickiness is also why your AR does not work either, same as https://doc.kodewerx.org/hacking_gba.html#nonstandard .

If it is a repurposed flash cart and you can figure out how to write it then you might be able to hardpatch the cheat in with something like https://gbatemp.net/threads/gbaatm-rebirth-gba-auto-trainer-maker-a-new-hope.564321/ but that is getting a bit radical at that point.

I have not looked up what the softlock is here either (I knew the one for 4 on the DS https://www.nintendo.com/consumer/systems/gameboy/trouble_specificgame.jsp but these I am less familiar with) but depending upon the nature of the softlock if reverting to an earlier save might cure it/allow a dodge then you might be able to force that if the game uses alternating save banks by turning off during saving but that risks everything.

If you or someone you know has one of those nice analogue pocket devices then you could actually snatch a savestate from that, edit the savestate (AR codes are just instructions on editing memory addresses, which you have the complete ones for by dint of having the codes) and restore that (I did something similar in https://gbatemp.net/review/analogue-pocket-gb-gbc-and-gba-handheld-fpga-based-player.2081/ ). It would probably have to be a device of that potency as well -- the more classical dumper-emulator combo that most historical clones are will probably only get the menu you use to select the games.
I don't know what goes for hacked GB players these days but I could see a path there https://github.com/FIX94/gba-link-cable-dumper/releases for a jumping off point, though it would take more work and basically be a custom dumper.

Re photos. If you can post one of the PCB (even on an external site and break up the url a la www . somesite . tld / blahnumbers , or say whatever image host and the unique bits so we can reconstruct it) I and probably several others would be interested; what you describe is a step above what we normally see for bootleg/pirate/repro carts, and indeed several vintage flash carts.

Thank you for such a comprehensive post! I have been busy so I haven't had time to respond. But I can post the url to it *snip*

The soft lock essentially involves the impossibility of getting 2 battlechips that are necessary to unlocking a gate that would give you another battle chip that would make it actually possible, eventually, to get those 2 battlechips necessary for unlocking the gate. Rockman EXE Zone put it perhaps more eloquently:

The Japanese version of the game contains a progression-halting oversight that can occur if you accept the "Self Request" Request BBS before opening the gate to Graveyard 2.

Finishing said quest requires a copy of the Anubis chip, which is obtained exclusively in Graveyard 2. However, opening Graveyard 2 requires that you obtain all Mega class chips, which includes all of ProtoMan's chips; but to fight ProtoMan SP, you need to have finished the bottom 25 quests on the Request BBS. Once you've accepted the Self Request BBS quest, you cannot complete any other quests until you finish it, which you cannot do if Graveyard 2 is inaccessible, so the quest becomes impossible to complete normally.

To get out of this situation, the player must trade a ProtoManEX and ProtoManSP from another game. If they cannot trade, the only remaining option is to try and get ProtoManEX from the Green Town Chip Trader Special, and get ProtoManSP from Graveyard 1 Gold Mystery Data.

Essentially I have three routes:
1) Man through the soft lock and get the 2 battlechips through the in-game lottery system. I have been doing this, according to the game clock, for >34 hours and I'm not any closer to getting them than I was at any other point. It is insanely time-consuming.
2) Trade the chips over from another game. As a matter of fact, I have multiple carts of this game --- the NA versions, though. The Collection's version of BN6 is actually EXE6, but patched over in English. It cannot trade with English versions. If I could use a flash cart to make an impromptu EXE6 cartridge, I could trade the chips over. I have two GBA SP and a working trade cable.
3) Use an outside device, like AR, to use the code a user made that allows you to examine something and instantly get the two necessary chips. I've already ordered an allegedly-functional AR. If it works on this cartridge, it will be the cleanest and fastest solution.

As for route 2, I'd do this but I have an R4 flash cart and not a GBA flash cart, so (I'm told) I can't make a random GBA cart into the game EXE6. I'm told I would need a GBA flash cart, get EXE6 on it, then trade with the green Collection cart. Which can indeed trade with other GBA carts, but is still region locked I guess.

 

[FAST6191]

Links to bootleg cards is not ideal as it is not much better than linking to a CD full of ROMs, and does not have the PCB shot (could possibly make something out through the frosting, interesting to see translucent green as well, I am sure the pokemon set are going to be amused to see that).

Theoretically you would have a few other options, however none are easier than making a save dumper for the DS which is most likely to be a minor tweak over an existing one -- I don't know whether this multi cart will be a one that used part of the ROM (see link above on bootleg save dumping for one particular strain), be some kind of page setting affair (most old school flash carts) or something more like https://mgba.io/2015/10/20/dumping-the-undumped/ (also a good general idea of how you would set about finding the commands) but it is still likely to involve dumping the game (probably getting the menu), figuring out the command to set the game you want, dumping that and then getting the save command (which is likely just some odd command sent to the ROM or save area http://problemkaputt.de/gbatek.htm#gbacartioportgpio ).
I would not bet on the new AR working in the sense it would on an original cart for the same reason as the thing linked (if the baseline cart displays the menu first when booting and then selects a new area) but you might be able to twist the region troubled one into appearing as something else if the read of either the serial in the game or some part of the save lands in a particular area of memory to be sent along via link cable (you then making a cheat to have it appear as the other region, and hope whatever other differences don't trouble things).

One of those options is make a multiboot game that can trade a la

except as you have a GBA no custom hardware needed (beyond a multiboot cable).
No way you can cut down a GBA game (and I don't think they would have made a standalone battle mode for something like this like you might a racing game) to fit so it would be custom coded, however it only needs to respond with a prebaked list of commands or respond to whatever simple challenges there are*
Likewise save exploit could be an option and maybe get a bit more space but timeline to make such a thing is likely more than replaying the game at this point.

*I am curious what the region differences are and if it is something in the save rather than the ROM header. If it is a save based trouble then you might have some options there if you have a stock cart or something functionally akin to it in the bootleg world.

 

[Weltock]

Thanks again for those details. I am probably going to attempt to use the Action Replay if I do anything at all, as long as it can't corrupt the file just by being used for a simple code like the one I'm going to use.

I don't think I can use any solution that will require more than an elementary school level of intelligence. I've used R4 for some kind of save transfer once before, but I can't even get that to work right now: all the R4 cart gives me when it's booted is a Pokedex entry for Pikachu. So I won't be able to try most of what is being suggested unless somebody is willing to walk me through in baby steps, which I think would be too much of me to ask reasonably.

Anyway, I worked on the other BN6 version (Falzar) and got it up to and beyond where the previous Gregar version had been locked at, so I'm satisfied. If I can't unlock Gregar version from its soft-lock then it's not a bit deal, really.

Thanks again for your help. I'll respond later if I decide to go forward with one of these methods.

P.S. The walrus avatar is cool. Is that from the Archie Sonic comics? I seem to recall a walrus there.

 

[FAST6191]

I doubt it will corrupt the save as much as just not work.

As far as the avatar the original walrus was from Betty Boop Minnie the Moocher (skip to 4.27 if you want)



It was then redrawn for me, however yes I believe the Sonic comics were the inspiration for that one.