Flashing ntrboot (Custom Firmware)

For support in English, ask for help at Nintendo Homebrew on Discord.
If you appreciate this guide, I accept Donations through PayPal or Bitcoin.

Before proceeding, ensure you have read all of the information on ntrboot

Note that the flashcart will not be able to be used for its standard functions while the ntrboot exploit is installed on it. There are optional steps at the end of the ntrboot flashing instructions to remove it from your flashcart when you are done.

Note that in some rare circumstances, it may be possible for the flashing process to brick a counterfeit flashcart and render it permanently unusable. This is unlikely, but nevertheless only original listed flashcarts are supported. To reduce the chance of receiving a counterfeit card, it is recommended that you use a reputable site to buy your flashcart (such as NDS Card)

What you need

  • Your ntrboot compatible DS / DSi flashcart:
    • Either the Acekard 2i or R4i Gold 3DS RTS
  • Two 3DS family devices
    • The source 3DS: the 3DS family device that is already running some kind of custom firmware (such as boot9strap or arm9loaderhax)
    • The target 3DS: the device on stock firmware
  • The latest release of boot9strap (ntr boot9strap; not the devkit file)
  • The latest release of ntrboot_flasher

Instructions

Section I - Prep Work
  1. Power off the source 3DS
  2. Insert the source 3DS’s SD card into your computer
  3. Create a folder named ntrboot on the root of your SD card
  4. Copy boot9strap_ntr.firm and boot9strap_ntr.firm.sha from the boot9strap ntr .zip to the /ntrboot/ folder on your SD card
  5. Copy ntrboot_flasher.firm from the ntrboot_flasher .zip to the /luma/payloads folder on the source 3DS’s SD card
  6. Reinsert the source 3DS’s SD card back into the source 3DS
  7. Insert your ntrboot compatible DS / DSi flashcart into the source 3DS
Section II - Flashing ntrboot
  1. Launch the Luma3DS chainloader by holding (Start) during boot on the source 3DS
  2. Select “ntrboot_flasher”
  3. Select “Dump Flash”
  4. Wait until the process is completed
  5. Press (B) to return to the main menu
  6. Select “Inject Ntrboot”
  7. Press (Y) to proceed
  8. Press (R) for retail unit ntrboot
  9. Wait until the process is completed
  10. Press (B) to return to the main menu
  11. Select “EXIT” to power off the source 3DS

Continue to Installing boot9strap (ntrboot)

Section III - Removing ntrboot

This is an optional section that will allow you to restore your flashcart to its original state.

Do not follow this section until you have already completed Installing boot9strap (ntrboot) on the target 3DS.

  1. Launch the Luma3DS chainloader by holding (Start) during boot on the source 3DS
  2. Select “ntrboot_flasher”
  3. Select “Restore Flash”
  4. Press (Y) to proceed
  5. Wait until the process is completed
  6. Press (B) to return to the main menu
  7. Select “EXIT” to power off the source 3DS