Arm9loaderhax coupled with AuReiNand gives us lucky 3DS users the amazing option of running Custom Firmware on sysnand. The advantages of this are as follows:

• Much faster and more reliable CFW cold booting compared to menuhax + emunand
• Slightly faster CFW cold booting compared to arm9loaderhax + emunand
• Using 2GB of SD card space for emunand is no longer needed (but still recommended to keep a 9.2 emunand around)
• GBA ROMs only need to be installed once, since they run from sysnand now!

Most CFW users will already have a 9.2 sysnand which is usually kept as vanilla as possible, and then an emunand running a higher FW version (i.e. 10.5) booted through CFW. With arm9loaderhax and AuReiNand, we can now swap the firmware versions over so 10.5 runs directly on SysNand, and EmuNand is used only when 9.2 is really needed (e.g. for running decrypt9). This tutorial will walk you through the process of swapping your sysnand and emunand, and changing your arm9loaderhax to use AuReiNand in order to cold boot directly to a patched 10.5 sysnand.

This tutorial assumes the following:

• You have a 9.2 or below sysnand and CFW running an emunand of a higher firmware version
• You know how to verify a SysNAND backup using md5
• You know how to back up your sysnand, emunand and SD card
• You know how to access hax to get to the Homebrew Launcher
• You know how to install homebrew apps on your 3DS
• You know how to install CIAs
• You have already captured your OTP and built an arm9loaderhax installer
• You have FBI installed on your sysnand

I won’t explain how to do all of these as this guide is intended to be an overview of the process I used to swap my sysnand and emunand.


If you follow this guide and do not have a valid sysnand backup, you risk bricking your console and this may not be recoverable without a hardmod.

This guide involves updating your sysnand to 10.5. If you don’t have a reliable way of downgrading to 9.2 if you need to, don’t follow this guide. This means you need to be able to use arm9loaderhax to boot CFW, or have a hardmod and a NAND backup, if you want to undo this.

Do not attempt this procedure without a working arm9loaderhax installer. A hardmod is not required but is recommended.


You will need:

• Homebrew hax already set up and running on your sysnand
• CFW already installed with a working emunand
• Decrypt9
• EmuNAND9
• MiniPasta
  
• AuReiNand mod (do not install this yet)

If you already have arm9loaderhax set up to boot your emunand, you will need to remove it. This is because one of the needed tools, decrypt9, can only run from sysnand. Arm9loaderhax will prevent you from entering sysnand at all, so will need to be removed. I did this by restoring a vanilla 9.2 sysnand backup which I took from the console prior to installing arm9loaderhax.


Stage 0: Make a backup of your SysNand, EmuNand and 3DS SD card

Seriously, you’ll be glad you did if something goes wrong. This process involves a lot of messing around with both sysnand and emunand.


Stage 1: Dump EmuNAND partitions

1. Boot your 3DS to sysnand
2. Launch hax and run MiniPasta
3. When back at sysnand, launch hax and run Decrypt9
4. Go to “EmuNAND Options” and then “Partition Dump”
5. Dump each of the partitions with the exception of FIRM0 and FIRM1, pressing B after each one to return to the menu and dump the next partition
6. Press START to quit Decrypt9, and reboot back to sysnand

Stage 2: Downgrade EmuNand to 9.2

1. From sysnand, launch hax and run MiniPasta
2. When back at sysnand, launch hax and run EmuNAND9
3. Choose “EmuNAND Manager Options” and then choose “Clone SysNAND to EmuNAND”
4. Once this is complete, press START to reboot
5. From sysnand, launch hax and run TinyFormat to format SysNand and unlink NANDs
6. Once the system reboots, complete the initial setup without linking NNID
7. Once you are at the home menu, set your sysnand theme to red
8. Launch hax and run CFW to get into emunand
9. Once in emunand, set the theme to blue
10. Power off the 3DS

At this point, your sysnand and emunand should both be on 9.2, and you should have dumps of your original emunand. The purpose of setting the NAND colours to red and blue is to ensure you can tell which NAND you are in, since they are both at this stage running the same FW version and will look identical.


Stage 3: Update SysNand to AuReiNand CFW 10.5

1. Take out your 3DS SD card and put it in your computer
2. Replace the rei folder, arm9loaderhax.bin and ReiNand.dat in the root of your SD card with the ones from AuReiNand.
3. In the new rei folder on your SD card, place the firmware.bin and firmware90.bin from the FIRMs archive linked from the AuReiNand GitHib page
4. Create an empty file on the SD card in the /rei folder called updatedsysnand
5. Put your SD card back in your 3DS and boot it up to sysnand
6. Launch hax and run arm9loaderhax.3dsx to install the loader
7. If you get stuck on a message saying “Exploiting arm9…”, you can safely reboot your 3DS
8. The 3DS will reboot once this process is complete
9. You should now be in sysnand but running ReiNand. Verify that arm9loaderhax has been installed by powering off your 3DS, removing the SD card and powering on again. Your system should hang on a black screen because the arm9payload is not available. If your 3DS boots to sysnand without the SD card inserted, this means that arm9loaderhax has not been installed properly and you MUST NOT proceed
10. Once you have verified that arm9loaderhax is working, replace the SD card and power on your 3DS to boot to sysnand
11. Open System Settings set up your Internet connection
12. Update to 10.5 (seriously, don’t do it unless you’re certain the CFW is running by doing the SD card removal test in step 9. If you update to 10.5 without CFW up and running, you risk not being able to run any unsigned code, meaning you could end up stuck on 10.5 with no CFW)
13. Once the update is complete and the system has rebooted, enter System Settings to verify that you are now on 10.5

Step 4: Reinject emunand partitions to sysnand

This stage will make your new 10.5 sysnand how your emunand used to be

1. Power off the 3DS
2. While holding L, power the 3DS back on. This will boot into the 9.2 emunand
3. Launch hax, and run Decrypt9
4. Choose “SysNAND Options” and then “Partition Inject”
5. Inject each of the partitions in turn, with the exception of FIRM0 and FIRM1, pressing B after each one to return to the menu and inject the next partition
6. Press START to quit Decrypt9 and reboot back to SysNand.

If everything went according to plan, you should be looking at your sysnand but with all your CIAs showing. In my case, they were all back in presents and out of their folders which was a mild inconvenience. I also lost my custom theme, so that had to be reinstalled.


Final checks

1. Launch a CIA from sysnand to verify that it works. Successful launching of a CIA will indicate that the sysnand CFW is working
2. Enter System Settings from sysnand to confirm that you are on 10.5
3. Power off your 3DS, and power it back on while holding L. You should then be booted to your emunand, which will resemble your sysnand before the swap over
4. Enter System Settings from emunand to confirm that it is on 9.2
5. Now, do another sysnand, emunand and SD backup!

 

[Svaethier]

I think the danger is of updating sysnand to 10.5 without getting arm9loaderhax working properly. That would leave you stuck on 10.5 with no CFW.

never had to reset up my a9lh at all plus injecting my 10.5 emunand ctrnand partition made my sysnand 10.5 but with my emunand stuff in it

 

[James310]

In the future when 10.6 is released...does aureinand need to be updated to work with it

 

[Svaethier]

In the future when 10.6 is released...does aureinand need to be updated to work with it

We're not sure but probably not.

 

[stl25]

Great write up @mashers. This is great for some of the valid points your detailed in your write up. If SD/microSD free space was an issue I would probably try it. I got a 128GB Sandisk microSD @bestbuy for about $60 bucks maybe a month or so ago, so I prefer the emuNAND to be updated to the latest FW version as it is easier to remedy for me and others who have no hardmod or will not get one unless they brick. AuReiNand is awesome and I can't wait to see Rei's next release that will bring back sysNAND. Despite my personal opinion this will appeal to many other members of this forum. Keep up the great work.

 

[peteruk]

very nice guide, thanks mashers

 

[Audioboxer]

Thanks for this mashers. After thinking about it I am just going to stay on 9.2 sys / 10.5 emu for now.

 

[dkabot]

EDIT: dark_samus confirmed that you just need to swap CTRNAND (though you may want AGBSave if you had GBA saves) and don't need to downgrade.
Here's the post, which contains even less steps than below.

I can confirm swapping them works, but I followed a slightly simpler set of steps.

Start: AiReiNAND latest is running thorough A9LH, 9.2 SysNAND and 10.X EmuNAND. Backups exist of both for safety but are not directly used should it work.

• Use SysUpdater on EmuNAND to downgrade it to 9.2
• Run SysNand with 9.0 FIRM (hold L on boot, needs latest AuRei)
• Open Decrypt9, backup all partitions of both NANDs that aren't FIRM
• Inject SysNand partitions into EmuNAND
• (Optional) Reboot now to make sure it worked, since all you changed so far is EmuNAND
• Inject EmuNAND partitions into SysNand
• Eject SD or shut down and add updatedsysnand flag to rei folder on SD
• (Re)Boot, update SysNand, and you're done

Of course, there's only one safety check in these steps, but so long as you're sure of what you're doing it's pretty easy.

 

[Svaethier]

I can confirm swapping them works, but I followed a slightly simpler set of steps.

Start: AiReiNAND latest is running thorough A9LH, 9.2 SysNAND and 10.X EmuNAND. Backups exist of both for safety but are not directly used should it work.

• Use SysUpdater on EmuNAND to downgrade it to 9.2
• Run SysNand with 9.0 FIRM (hold L on boot, needs latest AuRei)
• Open Decrypt9, backup all partitions of both NANDs that aren't FIRM
• Inject SysNand partitions into EmuNAND
• (Optional) Reboot now to make sure it worked, since all you changed so far is EmuNAND
• Inject EmuNAND partitions into SysNand
• Reboot, update SysNand, and you're done

Of course, there's only one safety check in these steps, but so long as you're sure of what you're doing it's pretty easy.

Exactly what I told you to do

 

[dkabot]

Exactly what I told you to do

Of course, it's a nice set of steps =P

Just saw this thread used a different set and wanted to add it in here for the record.

Edit: Wait a sec, what is mini pasta even used for? It's just sig checks, but EmuNAND9 isn't a CIA. It should be able to just run from hax.

Double edit: I know the AuReiNand with "hold L for SysNand" only really happened yesterday, but "remove A9LH if you have it" is really inefficient. Hopefully this gets cleaned up to reflect the new stuff.

 

[shaneod]

If you already have arm9loaderhax set up to boot your emunand, you will need to remove it. This is because one of the needed tools, decrypt9, can only run from sysnand.

I held L on AuReiNAND and it seemed to boot to sysNAND. I copied Decrypt9WIP.3dsx to SD root and then renamed it to boot.3dsx.
Then I ran OOT3DHax and it booted up Decrypt9, and I still have arm9loaderhax installed.
I'm backing up my emuNAND right now to verify, but I'm pretty sure it's working, no?

As a side note, if I had not renamed Decrypt9 and attempted to launch it from the homebrew launcher, I would have just got a black screen.
All homebrew launched from the homebrew launcher in AuReiNAND sysNAND seems to be giving a black screen, weirdly.

Edit: Nevermind. It seems others have come up with a less convoluted solution than the one I'm trying.

 

[mashers]

I held L on AuReiNAND and it seemed to boot to sysNAND.

Make sure you're using the latest release of AuReiNand. The shoulder button triggers were messed up on previous releases.

 

[conradcervantes]

Contemplating trying this since space on my 64gb is becoming precious, but it was a chore just getting it to coldboot emunand.

 

[dkabot]

Contemplating trying this since space on my 64gb is becoming precious, but it was a chore just getting it to coldboot emunand.

Honestly, you'd prolly want the 9.2 emunand around Just In Case(TM), only direct benefits I see here are GBA games only need one install and you can use multiple cards (so long as they all have AuReiNAND configured)

 

[mysamdog]

How many tries did it take you guys for the a9lh installer to work? Mine gets stuck at Exploiting ARM9 every time I launch it.

 

[PedroPVJ]

LOL just did the swap and now i have no cartridge app
----

nvm

 

[mysamdog]

Just a FYI for anyone who had the same problem as me (stuck on exploiting arm9), I fixed it by building delebile's repository instead of capito27's (I used the firmware and secret sector files from capito27's repository) and running it from minipasta

 

[Svaethier]

LOL just did the swap and now i have no cartridge app

you did something wrong then.

 

[Supster131]

you did something wrong then.

Instructions aren't clear enough, my 2DS became a 3DS.

 

[Svaethier]

Instructions aren't clear enough, my 2DS became a 3DS.

lol, the instructions are very clear

 

[DigitalJosee]

After swapping the NANDs, can I completely remove the emuNAND from my SD Card?