20 CFW emuMMC setup unpatched
KudbiOdd edited this page 2026-06-29 00:55:21 +09:00
Table of Contents

How to set up CFW and emuMMC for an unpatched Switch (Erista)

This page is for setting up CFW for an unpatched Switch console which uses the RCM exploit to inject payloads to start CFW. And creating an emuMMC with Nintendo connections blocked.
Afterwards you will have a good setup to keep using sysMMC as before, for eShop and playing online. While the separate emuMMC can be used when needing to install homebrew games, forwarders and game backups you've dumped.

Notes

No SD reader needed (click to expand)
Disable cloud saves and automated backups (click to expand)
  • If you don't have NSO or never enabled cloud saves, it's disabled.
  • How to:
    • Open HOS Settings(System Settings) ➔ Data ManagementSave Data CloudSettings and disable Automatically Back Up Save Data and Automatically Download Save Data
  • This can be turned back on again on sysMMC after creating emuMMC.
  • Partition or file emuMMC: You can read here about the benefits of both, so that you may later decide on which emuMMC type to pick.
    • If unsure choose partition, it is the better option.
  • Auto RCM: This guide will have you enable AutoRCM by default. Once you've used Hekate to enable it, the console will always go into RCM when turned on. Making the "jig" not needed unless AutoRCM is removed/disabled.
  • Never exFAT with Switch: Once you have completed setting up your device, ensure that you never format your SD card to exFAT. exFAT users are much more likely to experience SD card corruption than FAT32 users. This is a Switch, HOS specific issue.
  • Mac/Linux users: If using a Mac remember to always use Hekate's "Fix Archive Bit" tool after copying files to your micro SD card. Mac often does a minor bit change to files/folders causing issues for the Switch and those files/folders will not show.
    • From Hekate's main menu press:
      ToolsArch bit • RCM • Touch • Pkg1/2folder ico Fix Archive Bit

Step 0 - Getting ready

Checklist

  • Unpatched Switch (Unpatched Erista model)
  • a PC and a USB-C cable (or an alternative way to inject payloads and getting files onto the micro SD card)
  • A micro SD card reader or TegraRCMgui and your Switch, see notes
  • 64 GB Micro SD card, or larger.
  • 30 GB free space on your micro SD card
  • Cloud saves disabled, see notes
  • CFW files

CFW files you need

Everything you need to download. (On GitHub scroll down and find the file under Assets)

Step 1 - SD backup

  1. Backup of all files from your micro SD to a PC (if it was used for the same Switch)
  2. When backup is complete delete all files on your micro SD card

Step 2 - CFW files to micro SD

Extract the following to the root of your micro SD card:

  • bootloader folder from the hekate_ctcaer_*.*.*_Nyx_*.*.*.zip
  • atmosphere-*.*.*-xxxxxx-*********+hbl-*.*.*+hbmenu-*.*.*.zip
  • patch-x.x.x-xx.x.zip

Step 3 - Hekate launch options

  • This configuration gives you 2 launch options:
    • CFW emuMMC - Atmosphere - for emuMMC that loads patches and blanks prodinfo.
    • Stock - for sysMMC without Atmosphère.
  • If you want to use Atmosphère on both sysMMC and emuMMC, you'll need an additional launch option for that.
  • It also sets a Hekate setting to make Hekate the reboot payload. Meaning you'll restart to Hekate when you use Restart from the power menu. (Hold the power button for 3 seconds, then choose Power Options and select Restart)
  1. Create a file named hekate_ipl.ini inside of your /bootloader/ folder

  2. Copy (You can use the clipboard button top right 📋) and paste this within the file:

    [config]
    autoboot=0
    autoboot_list=0
    bootwait=3
    backlight=100
    autohosoff=0
    autonogc=1
    updater2p=1
    bootprotect=0
    
    [CFW emuMMC - Atmosphere]
    pkg3=atmosphere/package3
    emummcforce=1
    cal0blank=1
    kip1patch=nosigchk
    icon=bootloader/res/icon_payload.bmp
    
    [Stock]
    pkg3=atmosphere/package3
    stock=1
    emummc_force_disable=1
    icon=bootloader/res/icon_switch.bmp
    

Step 4 - Blocking Nintendo | Avoiding a console ban

≣ Notes about serial blanking and blocking connections: (click to expand)

📝 Both blanking the console's identifying serial information and blocking connections will be used

  • Atmosphère can blank serial info. This is enough to avoid a ban but using only this will cause a crash from version 1.7.0 of Atmosphère. We set this setting with both the cal0blank=1 line in the launch option, and also by having this exosphere.ini with the line blank_prodinfo_emummc=1.
    • Having both is redundant but not harmful, and makes user error less likely.
  • Atmosphère can block specified connections via it's built in DNS.mitm feature using a hosts file. This is the emummc.txt we'll add in this step.
  • Using the setup in this guide, Nintendo will only blocked while using emuMMC.

4.1 Blocking Nintendo connections

  1. Create a file named emummc.txt in /atmosphere/hosts/ (the hosts folder won't exist, so make sure to create it)

  2. And copy and paste this in your emummc.txt file: (You can use the clipboard button top right 📋)

    # Block Nintendo Servers
    127.0.0.1 *nintendo.*
    127.0.0.1 *nintendo-europe.com
    127.0.0.1 *nintendoswitch.*
    157.230.80.146 *conntest.nintendowifi.net
    157.230.80.146 *ctest.cdn.nintendo.net
    

4.2 Blanking serial info

  1. Create the file exosphere.ini in the root of your SD card

  2. Copy and paste this in your exosphere.ini file: (You can use the clipboard button top right 📋 )

    [exosphere]
    debugmode=1
    debugmode_user=0
    disable_user_exception_handlers=0
    enable_user_pmu_access=0
    blank_prodinfo_sysmmc=0
    blank_prodinfo_emummc=1
    allow_writing_to_cal_sysmmc=0
    log_port=0
    log_baud_rate=115200
    log_inverted=0
    

Step 5 - Injecting payload

  1. Create a folder named Hekate on your desktop (or name it whatever you want and place it where you want payloads) and extract hekate_ctcaer_x.x.x.bin from hekate_ctcaer_x.x.x_Nyx_x.x.x.zip into it. (where the x.x.x will be the version number)
    • This is the payload .bin file you'll use to start Hekate.
  2. Place your SD card back into your switch
  3. Enter RCM: Insert your RCM jig in the right side of your rail, hold volume up (Vol+ ico) button and press the power button (Power ico).
    • Once the Switch is in RCM the jig can be removed.
    • If you've used Hekate previously and enabled "Auto RCM" you simply press the power button (Power ico).
  4. Instead of the Switch turning on normally you get just a black screen, this is RCM. You are ready to inject a payload with one of these methods:
≣ Alternative A) Using a Windows PC: (click to expand)
  1. On your pc run TegraRcmGUI_vx.x_Installer.msi.
  2. Once installed, launch TegraRcmGUI. Once TegraRcmGUI is running, go to the Settings tab and click on Install Driver.
  3. Once the driver is installed, back to the Payload tab.
  4. Press the folder icon, and navigate to the folder named Hekate that you created and pick the file named hekate_ctcaer_x.x.x.bin.
  5. Connect your Switch to your PC, press Inject payload, and you'll launch into Hekate.
    • Make sure TegraRcmGUI is running, and injected the payload successfully.
      • (If you get Smashed the stack with a 0x0000 byte in TegraRcmGUI, then your switch is patched)
  6. Once Hekate has started on the Switch continue to Step 6 - Creating emuMMC and finish
≣ Alternative B) A payload launcher or other alternative: (click to expand)
  • If you're not injecting payloads from a Windows PC see the How to launch a payload page, for alternatives to TegraRcmGUI.
  • You will still use Hekate's payload file named hekate_ctcaer_x.x.x.bin.
  • Once you've injected Hekate successfully continue to Step 6 - Creating emuMMC and finish

Step 6 - Creating emuMMC and finish

Pick which emuMMC type you want to use. emuMMC partition (recommended), or emuMMC file.

Follow either alternative A or B:

≣ Alternative A) Partition-based emuMMC (recommended) and final instructions: (click to expand)
  1. Select the Tools tab, then select Partition SD Card, and finally press Ok.
  2. Move the emuMMC (RAW) slider until it says 29 full, then press Next Step and finally press Start.
  3. Once the operation is done, press Close and then select the Home tab.
  4. Select emuMMC in the main menu, then select Create emuMMC
  5. Select SD Partition and then select Part 1.
  6. Wait for your emuMMC to get created. Once its done, select Close and again Close.
  7. Select Tools then select Arch bit • RCM • Touch • Pkg1/2 and pick AutoRCM then Close when it's set after a second.
  8. Move back any previously deleted files into your SD card:
    • Connect the Switch to your PC and enable "USB Mass Storage in Tools" (see guide page) and move back any previously deleted files. Eject Switch safely and select CloseCloseHome in Hekate to get back to the main menu.
    • IF you instead turn your device off by pressing Power offPower off, and use the card reader you used earlier to move files back into your SD card. You'll have to inject payload again after you've placed your SD card back into your Switch.
  9. Once you're in Hekate, click on launch, and select emuMMC - Atmosphere CFW to launch emuMMC with Atmosphère.
    • If you need to go into sysMMC without your CFW, select Launch and then select Stock
    • If you want to use Atmosphère with both sysMMC and emuMMC, add an additional launch option to hekate_ipl.ini. See this section.
  10. You did it! You finished cfw and emuMMC setup.
  • Make a complete sysMMC backup if you haven't already.

  • Suggestion: After starting emuMMC for the first time, change system theme to white (or black) so it's different from sysMMC, and you'll have a simple visual to differentiate sysMMC from emuMMC.

≣ Alternative B) File-based emuMMC and final instructions: (click to expand)
  1. Select the Tools tab, then select Partition SD Card, and finally press Ok.
  2. Press Next Step and finally press Start.
  3. Once the operation is done, press Close and then select the Home tab.
  4. Select emuMMC in the main menu, then select Create emuMMC. Select SD File
  5. Wait for your emuMMC to get created. Once its done, select Close and again Close.
  6. Select Tools then select Arch bit • RCM • Touch • Pkg1/2 and pick AutoRCM then Close when it's set after a second.
  7. Move back any previously deleted files into your SD card:
    • Connect the Switch to your PC and enable "USB Mass Storage in Tools" (see guide page) and move back any previously deleted files. Eject Switch safely and select CloseCloseHome in Hekate to get back to the main menu.
      • IF you instead turn your device off by pressing Power offPower off, and use the card reader you used earlier to move files back into your SD card. You'll have to inject payload again after you've placed your SD card back into your Switch.
  8. Once you're in Hekate, click on launch, and select emuMMC - Atmosphere CFW to launch emuMMC with Atmosphère.
    • If you need to go into sysMMC without your CFW, select Launch and then select Stock
    • If you want to use Atmosphère with both sysMMC and emuMMC, add an additional launch option to hekate_ipl.ini. See this section.
  9. You did it! You finished cfw and emuMMC setup.
  • Make a complete sysMMC backup if you haven't already.

  • Suggestion: After starting emuMMC for the first time, change system theme to white (or black) so it's different from sysMMC, and you'll have a simple visual to differentiate sysMMC from emuMMC.


All CFW setup guides 🦝