Installing boot9strap (ntrboot)

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Required Reading

To use the magnet links on this page, you will need a torrent client like qBittorrent or Deluge.

What You Need

  • A magnet that triggers the sleep mode of your device (if using a folding style device)
  • Your ntrboot flashed flashcart
  • The latest release of SafeB9SInstaller (direct download)
  • The latest release of boot9strap (direct download)
  • The latest release of Luma3DS (the Luma3DS .zip file)

Instructions

Section I - Prep Work

  1. Power off your device
  2. Insert your console’s SD card into your computer
    • This is the SD card from your 3DS, not the SD card from your flashcart
  3. Copy SafeB9SInstaller.firm from the SafeB9SInstaller .zip to the root of your SD card and rename it to boot.firm
    • The root of the SD card refers to the initial directory on your SD card where you can see the Nintendo 3DS folder, but are not inside of it
  4. Copy boot.3dsx from the Luma3DS .zip to the root of your console’s SD card
  5. Create a folder named boot9strap on the root of your console’s SD card

  6. Copy boot9strap.firm and boot9strap.firm.sha from the boot9strap .zip to the /boot9strap/ folder on your console’s SD card

  7. Reinsert your SD card into your 3DS
  8. Power on your device

Section II - ntrboot

  1. Use the magnet to find the spot on your device where the sleep sensor is triggered
    • This step is not needed on the old 2DS (which has a sleep mode switch)
  2. Power off your device
  3. Insert your flashcart into your device
  4. Place the magnet on your device to trigger the sleep sensor
    • On old 2DS, you should instead enable the sleep mode switch
  5. Hold (Start) + (Select) + (X) + (Power) for several seconds, then release the buttons
    • It may take a few attempts to get this to work because the positioning is awkward
  6. If the exploit was successful, you will have booted into SafeB9SInstaller
  7. Remove the magnet from your device
    • On old 2DS, you should instead disable the sleep mode switch

Section III - Installing boot9strap

In this section, you will install custom firmware onto your device.

  1. When prompted, input the key combo given on the top screen to install boot9strap
  2. Once it is completed, force your device to power off by holding down the power button
    • Your device will only boot to the SafeB9SInstaller screen until the next section is completed

Section IV - Configuring Luma3DS

  1. Insert your SD card into your computer
  2. Delete boot.firm from the root of your SD card
  3. Copy boot.firm from the Luma3DS .zip to the root of your SD card
  4. Reinsert your SD card into your device
  5. Power on your device1. Your device should have booted into the Luma3DS configuration menu
    • Luma3DS configuration menu are settings for the Luma3DS custom firmware. Many of these settings may be useful for customization or debugging
    • For the purpose of this guide, leave these options on the default settings (do not check or uncheck anything)
    • If your device shuts down when you try to power it on, ensure that you have copied boot.firm from the Luma3DS .zip to the root of your SD card
  6. Press (Start) to save and reboot

At this point, your console will boot to Luma3DS by default.

  • Luma3DS does not look any different from the normal HOME Menu. If your console has booted into the HOME Menu, it is running custom firmware.
  • On the next page, you will install useful homebrew applications to complete your setup.

Continue to Finalizing Setup

The following is an optional section that will allow you to restore your flashcart to its original state (to allow it to be used for its standard functions).

Note that the Acekard 2i retains its ability to launch .nds files while having the ntrboot exploit installed. This only applies when the Acekard 2i is in an NDS or custom firmware 3DS! While the ntrboot exploit is installed to the Acekard 2i, it will be unable to launch .nds files on DSi or stock 3DS systems.

Do not follow this section until you have completed the rest of the instructions on this page.

Section V - Removing ntrboot

What You Need
  • The latest release of ntrboot_flasher (ntrboot_flasher.firm)
  • The flashrom backup corresponding to your flashcart
    • Note that if you followed Flashing ntrboot (3DS Multi System), the flashrom backup already exists in the correct location and does not need to be downloaded
    • Note that if you followed Flashing ntrboot (3DS Single System) or Flashing ntrboot (NDS), the flashrom backup already exists on your flashcart’s SD card and should be copied to the location specified below
    • If you do not know which HW revision you have, just try each for your cart of them. Only the correct one will allow your flashcart to launch properly from the HOME Menu, but flashing the wrong one will not brick the cart
Flashcart Hardware Revision Flashrom
Ace3DS X   N/A
Acekard 2i HW 81 - Acekard_2i_(HW_81)-Flashrom.zip
Acekard 2i HW 44 - Acekard_2i_(HW_44)-Flashrom.zip
DSTT   Missing
Infinity 3 R4i HW A5 - R4i_Gold_3DS_(HW_A5)-Flashrom.zip
R4 3D Revolution HW A6 - R4i_Gold_3DS_(HW_A6)-Flashrom.zip
R4i Gold 3DS Deluxe “Starter”   Missing
R4i Gold 3DS HW 4 - R4i_Gold_3DS_(HW_4)-Flashrom.zip
R4i Gold 3DS HW 5 Missing
R4i Gold 3DS HW 6 Missing
R4i Gold 3DS HW 7 Missing
R4i Gold 3DS HW 8 - R4i_Gold_3DS_(HW_8)-Flashrom.zip
R4i Gold 3DS HW D - R4i_Gold_3DS_(HW_D)-Flashrom.zip
R4i Gold 3DS Plus   N/A
R4i Gold 3DS RTS HW A5 - R4i_Gold_3DS_(HW_A5)-Flashrom.zip
R4i Gold 3DS RTS HW A6 - R4i_Gold_3DS_(HW_A6)-Flashrom.zip
R4i Gold 3DS RTS HW A7 - R4i_Gold_3DS_(HW_A7)-Flashrom.zip
R4i Ultra   - R4i_Ultra-Flashrom.zip
R4i-SDHC 3DS RTS   - R4i-SDHC_3DS_RTS_B9S-Flashrom.zip
R4i-SDHC B9S   - R4i-SDHC_3DS_RTS_B9S-Flashrom.zip
R4iSDHC GOLD Pro 20XX from r4isdhc .com   - R4iSDHC.com_20XX-Flashrom.zip
R4iSDHC RTS LITE 20XX from r4isdhc .com   - R4iSDHC.com_20XX-Flashrom.zip
R4iSDHC Dual-Core 20XX from r4isdhc .com   - R4iSDHC.com_20XX-Flashrom.zip
Instructions
  1. Power off your device
  2. Insert your SD card into your computer
    • This is the SD card from your 3DS, not the SD card from your flashcart
  3. Create a folder named ntrboot on the root of your SD card
  4. Copy the .bin file from your flashrom backup .zip to the /ntrboot/ folder on the root of your SD card
  5. Create a folder named payloads in the luma folder on your SD card
  6. Copy ntrboot_flasher.firm to the /luma/payloads/ folder on your SD card
  7. Reinsert your SD card into your device
  8. Insert your ntrboot compatible DS / DSi flashcart into your device
  9. Launch ntrboot_flasher by holding (Start) during boot
  10. Read the red screen warning
  11. Press (A) to continue
  12. Select your flashcart
    • If you do not see your flashcart in the list at the top, read the bottom screen for more info on each option
  13. Select “Restore Flash”
  14. Press (A) to proceed
  15. Wait until the process is completed
  16. Press (A) to return to the main menu
  17. Press (B) to power off your device