Dumping and backing up Wii U discs
The Wii U is Nintendo's third console that uses optical discs. Since the IOSU exploit was released it is possible to dump raw disc images with the Wii U. It's a very simple but time consuming process.
What you need
In the best case you already have everything required at home:
- A Wii U (du'h)
- An SD card (w/ 24GB of free space if you want to dump to it)
- Optional but recommended: An external USB disk drive if you want to dump to it instead
- A computer (Windows)
- An SD card reader if your computer has none integrated
- The disc(s) you want to dump
There's also some software required in order to prepare and finalize everything:
Before you can start a few preparation will have to be done in order to proceed. If you already have an SD card with the homebrew launcher installed you can skip to step 4.
- First you should convert your SD card and external USB disk to FAT32. Go here if you'd wish to see a guide on how to format a drive to FAT32 using FAT32-Formatter and h2format (to do).
- Once this is done create the following directory structure on your SD card:
(If you don't understand what this structure means, create a folder named wiiu on the root of your SD card. Then create a folder named apps inside of the wiiu folder.
- Extract the homebrew_launcher.zip to a new archive and copy the homebrew_launcher folder inside of it to the apps folder of your SD card.
- Unzip wudump.zip and create a folder named wudump inside of the apps folder of your SD card. Put wudump.elf into the wudump folder.
Dumping a disc
- Remove the SD card from your computer and insert it into your Wii U.
- If you want to dump your disc to USB plug in the USB drive into one of the front USB plugs of your Wii U.
- Stretch out your pointer finger and move it towards your Wii U. Make it touching the Power Button and press it until the red LED turns blue.
- If there's a game disc inside your Wii U's disc drive, eject it.
- Open the webbrowser and use your preferred method to load the Homebrew Launcher. If you aren't selfhosting everything I recommend going to loadiine.ovh and select Homebrew Launcher 1.3 (not 1.4 or higher). Then click submit. You should now land in the Homebrew Launcher.
- Now load wudump
- Choose whether you want to dump your game to SD or USB by either pressing A or B.
- After the IOSU exploit has been performed insert a game disc.
- Wudump should automatically dump the disc. This should take about 2 hours. When dumping to an SD card this may take a bit longer. The game will be split in 2GB files.
Merging the splitted dump to a single .wud file
We are not finished now. Because the max. file size of a FAT32 partition is 4GB wudump splits the game into 12 parts of 2GB in length. So we will have to merge them now:
- Insert the SD Card or USB drive back into your computer.
- Create a folder where you want to have your .wud image(s).
- Open the wudump folder on the root of your SD card.
- Right-click there and create a new .txt file. Rename it to merge.bat.
- Right-click the merge.bat and click on edit.
paste: copy /b game_part1.wud + game_part2.wud + game_part3.wud + game_part4.wud + game_part5.wud + game_part6.wud + game_part7.wud + game_part8.wud + game_part9.wud + game_part10.wud + game_part11.wud + game_part12.wud <destination>\game.wud into notepad and replace <destination> with the path of where you want to save the .wud file. and save the file.
- Double-click the merge.bat and let it merging the file to your directory. You should then be left with a .wud file with the size of 23GB.
Such a .wud file can be played with Cemu. Do not delete the common.key and the game.key. These are keys needed in order to play the game with Cemu. Both are also needed if you want to extract the game with wud2app.