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If you have any questions see the Gateway 3DS FAQ and 3DS Hacking FAQ or post your question in this thread - 3DS - Ask questions here

Installation

Things that will be needed in the installation:

  1. The Blue and Red Cards from Gateway
  2. 2 microSD cards, the larger should preferably be used for the Red Card unless you want to have huge DS Library
  3. The SD card that the 3DS uses for user data.

Copying Files and Backing Up the SD card

Format the microSD card you plan to use in the Blue Card as FAT32 (Right Click -> Format -> File System) and the microSD you plan to use in Red Card as exFAT First download the latest Gateway firmware off the Gateway website or a mirror (if you wish to update the sysNAND to 4.5 without the use of a retail cart stop and read (foobar).

After uncompressing the Gateway firmware download copy everything inside "Blue Card (R4i)" to the root of microSD you plan to insert in the blue card. Backup the entire SD card onto a computer, then copy the file Launcher.dat to the root of the SD card

Using the Gateway Installer

Insert the blue card in the 3DS and run the Deep Labyrinth (Sword Icon) that appears, this should open up a file explorer for your Blue Card's storage, navigate to the Gateway Installer, execute it and follow the instructions. The installation may sometimes hang, hold the power button to switch off the 3DS and try again If installation succeeds follow the power off prompt.

Backing up your sysNAND and creating an emuNAND

Insert the Red Card and switch on the 3DS, enter the Settings menu, then the Other Settings menu, the Profile Menu and finally hold the L button while pressing Nintendo DS Profile button. The Gateway logo then the Gateway menu should appear if not, power off the 3DS and try again. Choose the backup NAND option, this will take a while. After the backup is done power off the 3DS and then copy the backup to a safe place. Enter the Gateway menu again as shown above, this time

Usage

Playing 3DS Games

Playing Online with 3DS Games

Playing DS Games / Running DS Homebrew

Usage