Because I'm a no-life, I decided to expand a crapton on everything here and just summarize everything talked about here. Although note that this might be inaccurate because I suck balls with pretty much any homebrewing scene that's not the Wii U lol. And also know that this is a slightly modified version of an old comment I made... which is a slightly modified version of zeron88's guide on how to do this (or at least that was their name before they got content deleted...). The reply thread of the comment I'm tweaking can be found
here.
Another thing: I'm pretty sure you can add modded NDS/DS save files this way AND use this method with DSVC games that are user-made/isn't available in the eShop. Heck, if you convert it correctly even saves from other emulators/a 3DS will work too! So for anyone else who needs help with this specific issue, you can try to use this guide as well.
SETUP (AKA what you'll need):
- Your ripped .sav file on a working PC with the ability to edit the file extensions (If you're using the stock File Explorer that comes bundled in with Windows 10/11, then you may need to
unhide file extensions before proceeding)
- A working copy (legal or not-as-legal) of the DSVC version of whatever game you're trying to transfer (in this case being your "Something, something eleven" game)
- A homebrewed Wii U with fully working system settings (Specifically the data management part of it)
- A minimum of 10 minutes of your time (up to 1 hour if you work rrrreeeeeeeaaaaalllllllyyyyyy slow and possibly even 1+ hours if you run into a serious issue). It's not that hard and it's something you can probably memorize after running through it a couple times.
- A homebrewed Wii U with fully working system settings (Specifically data management) es should be the files for SaveMiiMod5 homebrew or a newer version of that (the download for that can be found on the homebrew AppStore or it can be manually downloaded
here (note that clicking on the link will automatically start the file download to your computer)). While you might be able to use Saveiine, this guide is centered around using the newer and much better SaveMii
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INSTRUCTIONS:
- Play the game on the DSVC and speedrun to the nearest point you can save the game as the DS game originally intended for you to save it.
- It doesn't matter how much of the game you get done, but it is crucial that you legitimately save the game or let the game autosave for you. I'm not too sure that loading/restoring savestates count as saving the game, so don't use this as a first resort. Rather, only try this if saving the game regularly doesn't create a save file.
- I believe that you can verify that you have created save data by checking for it via data management in system settings
- Safely exit the DSVC game and make a backup of the DSVC's save file using SaveMii, Saveiine, or whatever save editor you're currently using. In case I wasn't clear already, make sure the backed up savedata is on your SD card! After you've acquired the goods, take the SD card out of the Wii U and chuck it into your PC.
- Things to note before moving on:
- As you probably know, messing with an HDD that's been formatted for Wii U use while it's not plugged into the Wii U is basically suicide to whatever content is currently on it. So don't make the save editing tool your computer!
- Don't bother having the save game you want to transfer on your SD card yet. Keep it on your PC!
- Before doing anything, be sure to make a copy of the original .sav file in case something bad ever happens to it. I don't think any harm will come to it, but it's better to be safe than sorry!
- Go into the newly backed up save folder that should be on your SD card via your file editing tool and delete any file inside it that has ".state" as its extension. Leave everything else alone!
- The save folder is usually copied to SD:\wiiu\saves\DS VC\[insert a string of 8 numbers here]. If isn't there, then I'm afraid you'll have to go hunting for it!
- Look for any file that has the ".save" file extension on it, and scribble down its full name AND file destination for later use. Then, delete that file
- Go to the saved game on your PC and change the name of the file you want to eject into the Wii U to exactly match the ".save" game you deleted in the last step. And when I say everything, I mean everything-- extension included (AKA change the ".sav" extension of the game to ".save")!
- If you're on Windows 10/11, then this is a friendly reminder to make sure you have domains/extensions unhidden so you don't name it to "[file name goes here].save.sav" instead of "[file name goes here].save"!
- And for any user, regardless of file editor, this is a friendly reminder to duplicate the original .sav file before changing it in case you need it later!
- If you haven't already, copy your new .save file to the same place where the old .save file was located on your SD card. After ensuring that everything is in order, eject your SD card safely and chuck the SD card back into your Wii U.
- Before you go back to your save editor, there's something else we need to do first. Navigate to the System Settings app on your Wii U and find the data management section. After that, navigate to wherever your chosen DSVC game is saved and delete its save data for only the profile you're planning on using! Deleting anymore than that is kind of a jerk move to anyone else also using the Wii U.
- Exit System Settings and boot up SaveMii or whatever save editing tool you're using. Then, recover the savefile you have edited or press whatever button it is to reinject your savefile to the Wii U.
- You should be done!
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Exporting Wii U saves to a DS/NDS:
If you want to transfer it back to ".sav", then all you need to do is copy the save file to your SD card and rename the file extension to the name it had before! In fact, the name of the game doesn't really matter as long as you rename the extension back to ".sav". To be safe though, I'd just rename it back to what it was before in order to guarantee it works.
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Troubleshooting:
- My DS save file is .drc or one of the other numerous save file types that's not .sav! What should I do???
- Use Shunyweb (it's a website, not an executable) to covert from whatever file type you have (find it in the dropdown of the "Source" Category) to whatever the .sav file size should be (i.e 64k, 32k, 8kb, or 0.5kb). If you aren't sure, then leave the default setting of acekard rpg / ez flash v / raw format [autodetection] (.sav)
- I thought I got my save file, but the progress is reset to 0%? What happened there???
- You may have not deleted the save data that you initially made at the start of the guide. Be sure to purge the old save data, then double-check by purging the data again via SaveMii or some other save file editor. Then, try again.
- I followed everything correctly, but SaveMii isn't picking up any savefile that's not on my SD card. Da heck did you do magic man???
- Before using SaveMii, make sure that CFW is enabled and if you have Tiramisu, make sure that 01_sigpatches.rpx (careful-- clicking on the link will download
01_sigpatches.rpx
!) exists and the file is in the right place (/wiiu/environments/tiramisu/modules/setup).
- I thought I did everything right, but literally nothing happened and it didn't work. Is this guide a secret government-issued propaganda designed to waste my time?
- If you really have followed everything correctly to a tee, then the only problem I can come up with is that your .sav file is omega padded. Basically, a save being padded means that the save itself is much bigger than it should be because the save is "padded" with a bunch of extra unneeded 0s or 1s. Usually, nothing happens, but in situations like these, it can screw saves so bad that not even the game will recognize them as saves and will literally delete and ignore them! You can usually tell if the save is padded if the save itself is like 500kb or some ridiculous number. I think the highest .sav files can be is 64kb, and even then you should double-check online how much space the .sav is supposed to take up.
- To fix this, you have a few options. First, you can try to trim the padded 0s off using something like godmode9 (if you have a 3DS), NDSTokyoTrim (for everybody else), or manually do it in a hex editor. You could also try to redo the dump with different dumping software and see if that would help. Finally, you can try to force the padded 1s and 0s out by compressing the .sav file to a smaller size using Shunyweb. Don't know if any of those 3 will work, but you can for sure try! Just remember to make a backup before you attempt anything.
- Note that looking at the reply thread of the original reply thread is a great place to answer questions that aren't listed here. And of course, you can always ask r/NDSHacks or here on GBAtemp for help too because they probably understand where questions like this much better than I can. If you do GBAtemp though, ask for godreborn and they will probably answer whatever questions you have about just about anything hacking-related. I think godreborn might actually be Jeebus reincarnated as an Indian IT tech support guy.
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Conclusion:
And there, is everything you should need for swapping DS games between a Wii U and an NDS. This was actually meant to reply to a Reddit post on
r/WiiUHacks, but it was too long so I'm posting it here instead. And thanks to that, some arts may sound off because this wasn't originally meant for this lol-- I just didn't want to discard 4 to 5 hours of work writing this up lol. And with that, I hope this helps!