SysNAND, EmuNAND, CFW and Pasta: a visual guide

Discussion in '3DS - Flashcards & Custom Firmwares' started by mashers, Feb 16, 2016.

  1. mashers
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    mashers Stubborn ape

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    Hi all

    We already have this great guide on emunand etc., but there's a lot of text and might be a bit intimidating for new users.

    https://gbatemp.net/threads/guide-the-emunand-save-data-mega-guide-gbatemp-doesnt-deserve.378491/

    So I decided to make a visual guide to help new users understand the basics.


    1. What and where is SysNAND,
    and what does it do?

    SysNAND is the name given by the hacking community to a chip inside the 3DS consoles. It is located on the 3DS main board inside the 3DS. The SysNAND contains the 3DS system software, including the home menu and all the other software required for the system to operate. This software also determines what the system can and cannot do. For example, the software on SysNAND prevents the user from installing homebrew or pirated software.

    SysNand.png


    2. What and where is EmuNAND,
    and what does it do?

    EmuNAND is a copy of the software contained in SysNAND. It is created for the purpose of removing the restrictions imposed by SysNAND. Once it has been created, it is located in a hidden area on the 3DS SD card. Like SysNAND, it contains the 3DS system software. Unlike SysNAND, EmuNAND can be modified to remove some of the restrictions. For example, the checks which prevent pirated software from being installed can be removed in EmuNAND.

    EmuNAND.png


    3. What does Custom Firmware (CFW) do?

    CFW is a piece of software for the 3DS which has two main functions:
    1. Switch the system from running on SysNAND to running on EmuNAND
    2. Patch various parts of the system software (in EmuNAND) such as removing the restrictions on the software which you can install and run, and removing the region locks
    Here is an overview of what happens when CFW is being used:

    CFW boot.png
    (click for a larger image)​


    There are three main CFW solutions:
    • rxTools
    • ReiNand
    • Cakes CFW
    After running the CFW launcher of your choice, your 3DS will no longer be operating in SysNAND, but will be running from the EmuNAND instead.


    4. What does Pasta CFW do?

    Pasta CFW patches some of the same system functions as the other CFW solutions, such as removing the restriction on what software can be installed and run. However, it makes these changes to SysNAND, not EmuNAND. After running the Pasta CFW launcher, your 3DS will reboot back to SysNAND, but with the ability, for example, to install and run CIA files.

    This is beneficial because certain CIA files need to be installed in SysNAND, such as other CIA installers, region free patches and GBA game ROM files.

    Here is an overview of what happens when Pasta is being used:

    Pasta Boot.png
    (click for a larger image)
    The most important thing to understand is that Pasta does not boot you to EmuNAND. If you run Pasta, you are still in SysNAND. This means that any changes or updates you make occur in SysNAND, not EmuNAND.


    5. When should I use SysNAND+Pasta,
    and when should I use EmuNAND+CFW?

    Pasta should be considered a temporary way of accessing a patched SysNAND. It should therefore only be used during the initial setup of EmuNAND, and briefly when a CIA needs to be installed to SysNAND (e.g. if installing a GBA game ROM file).

    For all other purposes including day-to-day game playing, EmuNAND should be used via CFW as the main way of using the console.


    6. How does all this relate to
    system software updates?

    It is vital to keep your SysNAND on a firmware version no higher than 9.2. Beyond this level, you will not be able to run CFW so cannot boot EmuNAND or even use Pasta. This means you should never, ever run system update from SysNAND, including if you have run Pasta. In either case, whether you are running Pasta or not, updating the system software from SysNAND will update SysNAND.

    Instead, you need to boot CFW first and verify that you are in EmuNAND. Then when you carry out a system software update, the update will be applied to EmuNAND instead of SysNAND.


    7. How to update EmuNAND safely

    Never perform a system update from a nag message offering to update. There are some reports of this updating SysNAND even if the user was in EmuNAND when the nag appeared. Instead, do the following to update your EmuNAND.
    1. Make sure your CFW is on the latest version, as some earlier versions of CFWs do not support the latest 3DS system software versions
    2. Boot into CFW+EmuNAND
    3. Open System Settings
    4. Verify that you are in EmuNAND. To do this, check the version number for its version string. It will look like one of the below:

      Rei.png RX.png
      (click for a larger image)

      Note that ReiNand (left) prepends "Rei" to the version string, and rxTools prepends "RX-E". Gateway EmuNAND prepends "GW3D".

      Note 1: If you are using rxTools and see RX-S, this means you are in SysNAND

      Note 2: If you are using Cakes CFW, you will see no difference in the version string and you will have to find another way to verify that you are in EmuNAND. A good strategy is to use a different home menu theme on EmuNAND and SysNAND so you can tell from the home menu which NAND you are in

      Note 3: If you are in any other CFW (ReiNand, rxTools or Gateway) and do not see the appropriate prepended identifier in front of the system version, this means you are in SysNAND and must not perform the update.

    5. Once you are sure you are in EmuNAND System Settings, go straight to System Update without closing settings. You should keep in mind that exiting System Settings will cause your 3DS to reboot, which will send you back to SysNAND if you don't have your 3DS to boot to CFW and EmuNAND when it starts up.


    8. Why is all of this so
    important to understand?

    With each system software update, Nintendo tries to patch the vulnerabilities which allow us to install unlicensed software and use other hacks. If you update SysNAND to the latest version of the system software, you will lost access to many of the best hacks available.

    Using EmuNAND allows you to keep up with the latest updates without losing access to these hacks. This is because you can keep your SysNAND on an exploitable version (e.g. 9.2), while having your EmuNAND updated to the latest version (e.g. 10.5). Because SysNAND is still exploitable, CFW will still be able to run and switch over to your EmuNAND.

    If you are not clear on the difference between SysNAND and EmuNAND, and also what Pasta does and does not do, you risk doing things like updating your SysNAND to the latest version when you meant to update your EmuNAND, which would result in losing access to your EmuNAND entirely.



    I hope this guide has been helpful to some new users. If any changes or additions are required please let me know!
     
    Last edited by mashers, Feb 16, 2016
  2. ihaveamac

    ihaveamac GBAtemp Guru

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    one thing I think you might like to add is "the safest way to update emunand":
    1. open System Settings
    2. check the version number to see if you are in emunand: RX-E for rxTools, Rei for ReiNand, GW3D for Gateway. (Cakes does not do this I think)
    3. go straight to system update without closing settings
     
    stoney05 likes this.
  3. mashers
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    mashers Stubborn ape

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    Good idea. Please could an rxTools and Gateway user send me a screenshot of the system settings showing the version string in system settings?
     
  4. 4ur0r

    4ur0r GBAtemp Fan

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    I still don't understand one thing: shouldn't emuNAND consume more battery than sysNAND?
     
  5. mashers
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    mashers Stubborn ape

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    Well it requires frequent access to the SD card to access the EmuNAND partition, so presumably it does draw a bit more current from the battery.
     
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  6. Urbanshadow

    Urbanshadow GBAtemp Maniac

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    Well, you know... CFW can patch signature patches on sysnand too (except reinand maybe?). The main thing about pasta cfw and rxtools pastamode (devmode) is that they boot sysnand without signature patches and without firmlaunch. Firmlaunch is what bricks you when trying to upgrade/downgrade with sysupdater.

    I mean, emunand is not necessary in any case but it is highly recommended because you can restore it with ease and any changes made to it make no effect to sysnand. As we still need sysnand correctly booting for menuhax reasons, it is important to have a healthy sysnand with access to everything needed to go CFW and/or emunand.

    I think there should be a place in here for Link/Unlinked nand differences. But overall great job.
     
  7. ihaveamac

    ihaveamac GBAtemp Guru

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    well I got screenshots for rxTools and ReiNand, if you want them. I don't have a Gateway red card so I can't the one saying GW3D.
    Warning: Spoilers inside!
    on a side note: rxTools sysnand is RX-S. it's not the same as pasta mode (which doesn't change the string).
     
  8. mashers
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    mashers Stubborn ape

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    Great, thank you! I was struggling to work out how to take a screenshot of System Settings even under ReiNand, so I appreciate you uploading both.

    Just to clarify, if you enter rxMode under SysNAND and then go to System Settings you will see RX-S? Is that right?
     
  9. ihaveamac

    ihaveamac GBAtemp Guru

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    yes, only for rxmode sysnand. I don't know if Gateway sysnand does anything similar.
     
  10. mashers
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    mashers Stubborn ape

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    Thanks mate. I didn't want to go into too much detail as it can become confusing. The main thing I wanted to get across in this guide was what the difference is between SysNAND and EmuNAND, and also the difference between Pasta and CFW. I hope that was clear enough, but please feel free to let me know if you think rewording is necessary.

    I will aim to add something about linked and unlinked NANDs.

    — Posts automatically merged - Please don't double post! —

    Thanks :)

    — Posts automatically merged - Please don't double post! —

    I've added a section on how to safely update EmuNAND. Thanks @ihaveamac for the suggestion and screenshots!
     
    peteruk likes this.
  11. Urbanshadow

    Urbanshadow GBAtemp Maniac

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    Not too much rewording in my opinion. Just keep in mind RxTools is the only one with region free, as reinand and cakes are region locked. (Not that really matters, as titles can be made region free and work on a region locked system) for point 4. It would be nice to state CFW is also capable of running patched sysnand but it's up to you.

    Then in section 5 or 7b could be nice to say pastaCFW and rxtools pastamode are the only way to go if a sysnand upgrade/dowgrade is completely necessary (no need to go into the firmlaunch thing).

    And be aware of cakesfw not having any version string mod.
     
  12. aos10

    aos10 how i fotochop?

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    so, after i run Pasta CFW , then restart my device, all change will gone?
     
  13. Urbanshadow

    Urbanshadow GBAtemp Maniac

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    If you mean the signature patches, yes. You will not be able to launch unsigned titles unless you run pasta again.

    Any title installed with FBI or BigBlueMenu during a pasta session will remain, as they are installed to sd and sysnand. You will not be able to run them without pasta, but you will see them installed. Also, theme data and personal configuration will stay.
     
  14. Bros.Life

    Bros.Life GBAtemp Regular

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    Why my emunand doesn't show the Rei's signature in System Settings? I'm pretty sure I am in emunand, however it just shows Ver. 10.5.0-30U. No "Rei" before the numbers.
     
  15. ihaveamac

    ihaveamac GBAtemp Guru

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    you probably have an older ReiNand which broke the "Rei" string. try updating it?

    https://github.com/Reisyukaku/ReiNand/releases
     
  16. Bros.Life

    Bros.Life GBAtemp Regular

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    Yeah, probably I have. To update it is just copy, paste and replace the old files in sd, right?
     
  17. ihaveamac

    ihaveamac GBAtemp Guru

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    replace the "rei" folder and "ReiNand.dat" file at the root
     
  18. Bros.Life

    Bros.Life GBAtemp Regular

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    Thank you! It worked very well.
     
  19. mashers
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    mashers Stubborn ape

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    I'll add that to the original post as I forgot that older versions of ReiNand don't show the prepended version string.
     
  20. andeers

    andeers Member

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    Why I can't install FBI over H&S on SYSNAND with Rxtools? I try, but the original H&S remains :s can somebody help me? (: