It's here!

​

Info

@Normmatt has created a way to run B9S .firm files from bootrom via a DSi Flashcard and a magnet! This works on every 3DS on any firmware version.

For installation without a PC, user @TheCyberQuake has created a pack which will automatically install B9S and copy over essential starter homebrew from the flashcard's SD to the 3DS's. This will mainly be used for PC-less B9S installations. If you have a PC with you, use 3ds.guide. Read more here: https://gbatemp.net/threads/481141/

How does this work?

This works because of a flaw in the bootrom. Before the bootrom boots the NAND, it checks to see if Start+Select+X is held down, and if the shell is closed. If these requirements are met, it will boot an NDS cartridge from the bootrom. This give that cartridge bootrom access. You might be wondering how you'd hold down buttons while the shell is closed, and why you need a magnet. If you put a magnet in a specific spot on the 3DS, it will go into sleep mode. Using this, you can boot the NDS cartridge with the buttons held down while in sleep mode! Using a reflashable flashcard, you can boot B9SInstaller using the flashcard, and easily install it on your 3DS.

The 2DS doesn't need a magnet since a switch puts it to sleep instead of a magnet.

What does this mean?

1. Any 3DS model on any firmware can be hacked with minimal effort
2. You can unbrick any 3DS model from any type of brick.
   - Remember, you don't need a NAND backup for this. Just do a CTRTransfer.
   - This does not apply to MCU bricks.
3. Even consoles with fried NAND, or even the NAND chip physically removed, can use this

This is incredibly impressive stuff, and will most likely be released soon! edit: now!

FAQ

Q: Can Nintendo patch this?
A: Nope! Not without a new hardware revision.

Q: My flashcard is blocked by my firmware! Can I still use this?
A: Yes! The flashcard blacklist is not enabled on the bootrom.

Q: Why can't this work with my flashcard?
A: The installation requires you to flash NTRBoot to the flashcard's nand. Most DS flashcards, such as the original R4, have a ROM, which is not flashable.

Q: Can I install NTRBoot on my flashcard without another 3DS system?
A: If you can run NDS roms on your 3DS with it, then yes. If it's blocked on your 3DS version, then you'll need another 3DS system to use it.

Q: Will my 3DS flashcard work?
A: No, only the NDSi flashcards listed above.

Q: Will any other flash cards work?
A: Only the ones listed in the OP. However keep in mind that flashcards such as the DSTT, Supercard DS2 and R4 SDHC Dualcore are planned to be supported in the future.

Q: I tried to do this with my cartridge and it didn't work?
A: It doesn't work with regular DS cards.

Q: Can I unbrick from a ____ brick?
A: Considering the card has access to the bootrom, yes! This can unbrick any brick (except MCU), unless you've taken a knife to the motherboard.

Q: Can I install B9S on the latest firmware with this?
A: Again, since the card has access to the bootrom, you can do this easily! Just plug in your flashcard, boot up using the magnet and button combination, and install.

Q: Does this work on the New Nintendo 2DS XL?
A: Yes!

Release
Guide
Free NTRBoot Flashing
Free B9S Installations

Here is SciresM's post about this

Please see SciresM's presentation on bootromhax.​

 

[jerbear64]

now i wonder if you could do something like the ds two and make a hacked 3ds more powerful by putting a cpu in a ds card

...what?

 

[Gamer4647]

now i wonder if you could do something like the ds two and make a hacked 3ds more powerful by putting a cpu in a ds card

You can't do it like that. Maybe extra memory, but not this.
I'd just make a homebrew that temporarily uses like 1GB of your SD card.

 

[jerbear64]

You can't do it like that. Maybe extra memory, but not this.
I'd just make a homebrew that temporarily uses like 1GB of your SD card.

Even if it *was* possible, the battery drain would be atrocious, and that's assuming the SLOT-1 even has enough power to maintain an extra CPU.

 

[Snooli]

Even if it *was* possible, the battery drain would be atrocious, and that's assuming the SLOT-1 even has enough power to maintain an extra CPU.

Well aside from this being off-topic AF, I also find interesting at least.
Modern ARM CPUs have very low consumption, so it wouldn't have to be so terrible. The biggest issue I see would be with data through-put. No add-in GPU I say. The best we could do is a CPU upgrade from O3DS to N3DS.

 

[SoslanVanWieren]

You can't do it like that. Maybe extra memory, but not this.
I'd just make a homebrew that temporarily uses like 1GB of your SD card.

Well you could the ds two does it for ds games

 

[failzers]

I'm surprised people still fall for Wierens bait.

 

[Byokugen]

I'm surprised people still fall for Wierens bait.

You don't think this magnet unbrick thingy is real"

 

[Deleted member 381889]

I was saying Magnethax unbricks. I mean't you can't just install b9s to a bricked one currently

pretty sure you can tho

 

[Billy Acuña]

I think Magnethax is a bad name since the magnet doesn't do anything at all.

 

[Deleted member 381889]

the magnet doesn't do anything at all.

but it puts the 3DS into sleep mode
I'd count that as something

 

[Billy Acuña]

but it puts the 3DS into sleep mode
I'd count that as something

I mean, it does not do anything hacky.

 

[Deleted member 381889]

I mean, it does not do anything hacky.

True
Some have been calling it NTRBootHax as well, and I've seen SleepHax being thrown around too haha

 

[dpad_5678]

Well you could the ds two does it for ds games

When someone more knowledgeable about a subject than you says You Can't, don't argue with them and say You Can. Jesus christ.

 

[Gamer4647]

When someone more knowledgeable about a subject than you says You Can't, don't argue with them and say You Can. Jesus christ.

Except I'm not really that knowledgeable. I just know that Game Cards just store game data, so shoving a CPU in it is unlikely to do anything. I also just take a peek every now and then at how things are doing.

 

[jerbear64]

Except I'm not really that knowledgeable. I just know that Game Cards just store game data, so shoving a CPU in it is unlikely to do anything.

Although, to be fair, the DSTWO does indeed have an extra CPU in it. It isn't the most powerful, and it drains the battery much quicker than a typical flashcart, but it's there.

It's not going to help boost the performance of the 3DS itself, though.

 

[Lacius]

True
Some have been calling it NTRBootHax as well, and I've seen SleepHax being thrown around too haha

+1 for SleepHax.

 

[dpad_5678]

Except I'm not really that knowledgeable. I just know that Game Cards just store game data, so shoving a CPU in it is unlikely to do anything. I also just take a peek every now and then at how things are doing.

Well you obviously seem to know that it would probably be impossible for 3DS mode software to be able to use the CPU inside the DSTwo.

+1 for SleepHax.

SleepHax for the community name, NTRBootHax for the technical name (like how Ninjhax was really MemChunkHax).

 

[Gamer4647]

True
Some have been calling it NTRBootHax as well, and I've seen SleepHax being thrown around too haha

+1 for SleepHax.

SleepHax is a simple name, and it's more consistent than MagnetHax when referring to the 2DS with everything else. Since I'm not really doing any 3DS hacking yet, idk what NTR even is, lol. Oh well.

 

[nl255]

Well you obviously seem to know that it would probably be impossible for 3DS mode software to be able to use the CPU inside the DSTwo.

I wouldn't say it is impossible, but it would be alot of work for very little gain. Not only would the DSTwo SDK have to be reverse engineered but it would also probably require adding support for arm9 access to cfw (which has been suggested multiple times but never done because it would be extremely hard to make it work). Thus, you would almost certainly see godmode9/decrypt9 available as a cia before seeing 3ds mode homebrew using the DSTwo CPU.

 

[TheCyberQuake]

+1 for SleepHax.

But the exploit has nothing to do with sleep mode, even if it uses the lid sensor that activates sleep mode.