Homebrew How can I make my own ctrnand file to use with any 3DS?

[assassinz]

I want to make a ctrnand of my old 3DS that I can use on any other old 3DS. Is this possible?

edit: Also want to know if I can I create a ctrnand from a sysnand file.

 

[Jjones]

Have you tried using Godmode9? https://github.com/d0k3/GodMode9/releases

 

[assassinz]

I checked Godmode9 and it only has the options to create sysnand and emunand. I don't see any option to create ctrnand.

 

[Jjones]

I'm pretty sure I saw it when I was making a nand backup to my computer, but i could be mistaken.

What do you need a ctrnand for anyway?

 

[Jjones]

maybe look at this? https://3ds.hacks.guide/ctrtransfer.html

 

[Jjones]

FYI you will need custom firmware on both of these DS's your working on.

 

[assassinz]

Checked that already and those ctrnand files are for region changing. And yes, I have cfw on my systems. Just trying to figure out how to generate my own ctrnand files.

 

[Jjones]

hmph, sorry i couldn't help. Good luck.

 

[assassinz]

Appreciate your input, thanks.

 

[Kwyjor]

I don't know where you checked in Godmode9, but you might be missing the relevant scripts. See for instance https://gbatemp.net/threads/release-godmode9-scripts-megathread.482150/page-9#post-8550543 .

Also, there's no reason you can't use the files in the Guide for things other than region changing if you wanted to.

 

[assassinz]

Kwyjor, after skimming through that thread it seems it is only showing how to do a ctrtransfer using an existing ctrnand file. I'm trying to find an option to do a ctrnand backup or create my own ctrnand*.bin file.

 

[Kwyjor]

Fair enough.

I think you can copy the CTRNAND image out of a NAND backup with ninfs, but I am not sure if the result has the same utility as the files linked in the Guide.

ETA: It should probably be emphasized that restoring a full NAND backup to a system different than the one that was originally used to produce the backup is one of the worst ways to brick a system.

 

[assassinz]

It wouldn't be a full nand backup of one system to another. But I want to compare a ctrnand file from my 3DS and see what the difference is from those ctrnand files for region changing that work with all 3DS systems. From what I understand, a ctrnand leaves out all the specific console files that a sysnand uses.

 

[The Real Jdbye]

A ctrtransfer backup is essentially a partial ctrnand backup, with console unique data stripped out. I'm not aware of an easy way to create one.
I'm not sure why you would need to make your own though. It essentially just contains the firmware files and nothing else. If you need a specific firmware version of ctrtransfer, there are other versions (than what is on 3ds.hacks.guide) available online. Can't think of any other reason why you'd want to make your own.

 

[assassinz]

I did a system transfer and saved the sysnand of my 3DS after the transfer. I wan't to create a ctrtransfer.bin file of a 3DS in a clean state before the system is setup, which is different than just formatting the 3DS.

 

[assassinz]

Where can I find other ctrtransfer files, other than the region changing ones on 3ds.hacks?

 

[The Real Jdbye]

You can't. Pretty sure a ctrtransfer doesn't contain save data like system setup. A lot of that is probably console unique or personal data so it wouldn't make sense to include it and even if you made a custom ctrtransfer image that included it, the actual ctrtransfer itself will ignore the extra files. ctrtransfer only copies the minimum needed folders to restore a bricked NAND to working or to downgrade. It's not designed to do what you're asking.

 

[assassinz]

So I was able to use decrypt9 to dump my ctrnand on my US system. I also found out that JPN systems that are region changed have corrupt or fragmented ctrnand and thus the ctrnand can't be dumped, according to the message in decrypt9. Does a corrupt or fragmented ctrnand mean that the sysnand will also be corrupt, even though sysnand on region-changed JPN systems can be dumped successfully?

I also found out I can use the 11.15.0 ctrtransfernand from my US 3DS to region-change a JPN 3DS.