Homebrew RELEASE ChoiDujourNX - a system firmware installer homebrew for the Nintendo Switch

[charlieb]

So, if I used this on my 5.1.0 Switch that I got on day 1, I could downgrade to 1.0.0, even if I've previously burned fuses?

no

 

[gallymimu]

AutoRCM subtly corrupts the BOOT0/1 partitions, forcing the Switch to enter RCM on each coldboot. That's all it does.

By forcing the Switch to enter RCM on each coldboot, it can't have the chance to boot normally and burn your efuses. It will always enter RCM, whereupon you will load Hekate, ReiNX, etc. in order to boot the OS without burning efuses.

OK thanks, I wasn't sure. So, you must inject a payload at each boot otherwise you will sit on a blank screen.

Is there currently a reverse utility?

 

[Lacius]

OK thanks, I wasn't sure. So, you must inject a payload at each boot otherwise you will sit on a blank screen.

Is there currently a reverse utility?

You can uninstall AutoRCM, but if you boot the Switch normally after that, you will burn your efuses and won't be able to to downgrade

 

[BlastedGuy9905]

hactool -x --intype=xci --updatedir=outupdatefolder Name.Of.The.Dump.xci
(you do not need ANY keys to extract xci with hactool)

Let me clarify something. You don't keys to extract XCI to anything (NCA's, update, whatever). Same goes with NSP. But when you extract the nca's inside an NSP, do you need keys or only the titlekey? What about nca's that come from XCI's? Do you only need a keys.ini in that case?

 

[TheZander]

no

Are you sure I thought it said it was possible.

--------------------- MERGED ---------------------------

• Q: I thought updating the firmware burned fuses, why would I use this instead of the official way of upgrading my Switch firmware (via cartridge or online, if I want the latest version)
• A: Because fuses are burned on first normal boot, not during the install. By default, ChoiDujourNX will enable AutoRCM on any flashed firmware image, meaning that the normal nintendo bootloader will never get the chance to burn the fuses. And therefore, you can downgrade any time you want back to the firmware you started from. You can also arbitrarily downgrade to whatever firmware you want, as long as you are not using the nintendo bootloader to launch it (which will burn fuses if not enough fuses are burned, and panic if too many fuses are burned, check the table here http://switchbrew.org/index.php?title=Fuses#Anti-downgrade).

 

[sp219]

Seem to be having some issues with SX OS -- I suppose this is to be expected since you don't launch the Homebrew menu the same way.. Works perfectly with Hekate though!

What issues are you having with SX OS?

 

[alucard_xs]

Are you sure I thought it said it was possible.

--------------------- MERGED ---------------------------

• Q: I thought updating the firmware burned fuses, why would I use this instead of the official way of upgrading my Switch firmware (via cartridge or online, if I want the latest version)
• A: Because fuses are burned on first normal boot, not during the install. By default, ChoiDujourNX will enable AutoRCM on any flashed firmware image, meaning that the normal nintendo bootloader will never get the chance to burn the fuses. And therefore, you can downgrade any time you want back to the firmware you started from. You can also arbitrarily downgrade to whatever firmware you want, as long as you are not using the nintendo bootloader to launch it (which will burn fuses if not enough fuses are burned, and panic if too many fuses are burned, check the table here http://switchbrew.org/index.php?title=Fuses#Anti-downgrade).

"Because fuses are burned on first normal boot"
If you boot your console on OFW, the efuses will be burnt.

 

[Draxzelex]

Let me clarify something. You don't keys to extract XCI to anything (NCA's, update, whatever). Same goes with NSP. But when you extract the nca's inside an NSP, do you need keys or only the titlekey? What about nca's that come from XCI's? Do you only need a keys.ini in that case?

All those keys are already within the Switch. External tools such as hactool needed to be fed these keys in order to extract Nintendo's dumped files because we were extracting from a device that doesn't have the keys.

 

[BlastedGuy9905]

All those keys are already within the Switch. External tools such as hactool needed to be fed these keys in order to extract Nintendo's dumped files because we were extracting from a device that doesn't have the keys.

But... The command I quoted doesn't need keys.

 

[anickname]

@rajkosto

Do you know if controller firmware upgrade is like cartridge firmware upgrade: once upgraded, not working anymore on lower OS firmware versions ?

Thank.

 

[gallymimu]

You can uninstall AutoRCM, but if you boot the Switch normally after that, you will burn your efuses and won't be able to to downgrade

Yup, I understand that. I was more concerned with whether there are different versions of AutoRCM and what tools can add/remove it. I simply haven't studied up on it so my apologies if it is a silly questions.

I'm close to going ahead and using the new tool to go from 4.0.1 to 4.1 (which wouldn't be any problem with fuses) or maybe up to 5.1 so all games work. I am just trying to make sure I have all the bases covered:

- if I go to a higher fuse versions, I should use AutoRCM to protect from fuse blow and game card controller changes.
- with autoRCM there is some risk of battery discharge if it goes into RCM and a payload isn't injected (a little scary but SHOULD be ok.)
- ability to launch any CFW SXOS, ReiNX, Hekate/whatevs through traditional RCM payload injection of choice.

 

[adrifcastr]

So, if I used this on my 5.1.0 Switch that I got on day 1, I could downgrade to 1.0.0, even if I've previously burned fuses?

Yes

no

Wrong.

 

[Draxzelex]

But... The command I quoted doesn't need keys.

There are something around 40 public keys which hactool uses to decrypt content. I'm not sure which content requires the remaining keys, but this is why hactool can decrypt .XCIs.

 

[BlastedGuy9905]

There are something around 40 public keys which hactool uses to decrypt content. I'm not sure which content requires the remaining keys, but this is why hactool can decrypt .XCIs.

The 40 public keys are copyrighted. That's why you need to get them yourself.

 

[Deleted User]

Where's the source? Not even touching this without being able to compile myself and see what it does. Also pretty sure this is based on GPL licensed code so not providing source is illegal

 

[masterzed]

that means i can update from fw 2.3 to 5 without burnings fuses. i'll been stay at 2 fuses? downgrade made easyier?

 

[Deleted User]

Also it's suspicious that this needs debug SVCs. Why the hell does it need that?

 

[alucard_xs]

Yes

Wrong.

?

 

[gallymimu]

Also it's suspicious that this needs debug SVCs. Why the hell does it need that?

Where's the source? Not even touching this without being able to compile myself and see what it does. Also pretty sure this is based on GPL licensed code so not providing source is illegal

Try asking nicely rather than being so fractious. You'll get a lot more of what you want that way.

 

[adrifcastr]

?

?