​

The Wii U was truly the black sheep of the main Nintendo consoles, but in terms of homebrew capabilities, it was but a diamond in the rough. While the Wii U is way past its heyday by almost a decade, the homebrew community still continues to thrive and develop great things for the system.

One of these developers, @shinyquagsire23, has made some research and advancements towards creating a modchip for the Wii U, which he titled "de_Fuse". The modchip started when Shiny Quasire started looking at the then unhacked Wii Mini console, in an attempt to glitch boot0 on it, and while getting curious if it could work on Wii U, he found that a similar exploit could be attempted for it, with the only downsides being OTP dumps being impossible due it being all 00s and the driver for boot0 being limited to SDHC cards.

While the necessity of having a modchip for the Wii U is not a must since Wii U already has coldboot exploits and many other things like Aroma that could serve a similar purpose, the main purpose of this modchip is to allow booting a Wii U console straight from the SD card, without having to rely on the Wii U's internal eMMC chip to boot into the console. This due to the recent news about some Wii U consoles bricking entirely due to failures in the eMMC chip, so giving players the option to boot from SD card would be a relief to this delicate issue that plagues the console.

​

The rest of the information is highly technical and dives into the eFuses, OTP, boot0, boot1 and SRAM of the console, so those interested in a more in-depth and detailed information regarding the process can read it in Shiny Quagsire's own article about de_Fuse on his webpage.

The modchip is currently in early stages of development, and it currently requires an FPGA of sorts, but it hasn't been standardized in terms of schematics or parts. However, Shiny Quagsire is trying to aim for a $25-$35 dlls range when its finished (or lower), based on RP2040 chip. Those interested and willing to collaborate and help out throughout its development can do so through Shiny Quagsire's GitHub repository for the modchip, where he keeps all of the coding and research for it open source.

de_Fuse, the One True Pwn article
GitHub Repository

 

[Valery0p]

Most likely you're the only one interested in that firmware ))

Good morning, did you manage to update your console after making the nand copy?

 

[gorgyrip]

Good morning, did you manage to update your console after making the nand copy?

Hi. I decided to keep it like that. And vwii is working.

 

[fringle]

Can someone point me to a guide that shows the solder connections for de_fuse on both the wii u motherboard and the pico? Also wondering if this works on the zero as well or is it just the pico? Have a dead wii u coming next week and may need this in an attempt to recover it.

 

[gorgyrip]

Can someone point me to a guide that shows the solder connections for de_fuse on both the wii u motherboard and the pico? Also wondering if this works on the zero as well or is it just the pico? Have a dead wii u coming next week and may need this in an attempt to recover it.

You have the solder points on the github. Also I have posted in this thread pics with the location of the TP.
Yes, zero will work, I've used it, too.

 

[fringle]

You have the solder points on the github. Also I have posted in this thread pics with the location of the TP.
Yes, zero will work, I've used it, too.

Thank you, I just didn't seem to know where to look. After a little poking around I've seemed to locate it.

 

[retrospect]

Will it let us play Wii games in full HD?

 

[Valery0p]

No, this is completely out of scope. You are stuck with WiiU's native upscaling.
Even a 5 years old phone can run Dolphin emu in full HD btw.

/end offtopic

 

[voddy]

Can someone point me to a guide that shows the solder connections for de_fuse on both the wii u motherboard and the pico? Also wondering if this works on the zero as well or is it just the pico? Have a dead wii u coming next week and may need this in an attempt to recover it.

https://github.com/shinyquagsire23/wii_u_modchip/tree/main/pico_defuse
and the pics where to find the points:
https://gbatemp.net/threads/de_fuse...-by-shinyquagsire.630931/page-4#post-10135904 (in spoiler tag)

 

[Valery0p]

while we are at it, forgot to mention, new deFuse release:
https://github.com/shinyquagsire23/wii_u_modchip/releases/tag/v0.7

now includes stroopwafel with plugin support

 

[kitsune1324]

I've been trying to read through as much as I can so forgive me if I missed anything..
I have the pico soldered to the wii u, followed the instructions, using the latest de_fuse, connected the pico successfully to my pc and can read via serial.

When attempting to boot (as it's running through iterations) I am getting the following error codes: 00, c3, and f3. The final error is:
SD card not valid or inserted, doing a normal boot.
[pico] Changed state: WIIU_STATE_NEEDS_DEFUSE -> WIIU_STATE_NORMAL_BOOT.

I already checked and made sure each header is connected to the correct pads.

I'm testing w/ two identical 1gb micro SD cards (non sdhc) and the folder structure looks like the following:
├── fw.img
└── wiiu
└── ios_plugins
└── wafel_core.ipx

The SD cards were flashed with the boot1.img, then reformated as fat32 (as per instructions) with an allocation size of 4096 bytes and no label. then they had the fw.img and wiiu folders (see above) copied to the sd card(s).

Once a boot is attempted, the wii u seems to (at some point) reformat the sd card and I never get any video out of the console (The original issue is potential nand failure followed by a failed update which got stuck at 98%).


Any thoughts/ideas? Right now I'm going to flash the sd card with just the boot1.img and not reformat/copy any files over and see what happens.

Post automatically merged: Aug 15, 2023

No luck with the SD card just formatted w/ the boot1.img. Once the SD card not valid or inserted error appears I have to again reformat the sd card.

 

[SDIO]

What output do you see in the terminal / putty on the PC?
How do you format the card? Using just the built in format function of windows?

 

[kitsune1324]

What output do you see in the terminal / putty on the PC?
How do you format the card? Using just the built in format function of windows?

Here's what I see from putty

Error code: 00
Starting... 2977
Results:
02
01
03
04
06
08
0a
09
0b
0c
0e
0d
0f
13
14
16
18
1a
19
1b
1c
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
26
00
00
Error code: 00
Starting... 2976
Results:
02
01
03
04
06
08
0a
09
0b
0c
0e
0d
0f
13
14
16
18
1a
19
1b
1c
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
26
00
00
Error code: 00
Starting... 2975
Results:
02
01
03
04
06
08
0a
09
0b
0c
0e
0d
0f
13
14
16
18
1a
19
1b
1c
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
26
00
00
Error code: 00
Starting... 2974
Results:
02
01
03
04
06
08
0a
09
0b
0c
0e
0d
0f
13
14
16
18
1a
19
1b
1c
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
26
00
00
Error code: 00
Starting... 2973
Results:
02
01
03
04
06
08
0a
09
0b
0c
0e
0d
0f
13
14
16
18
1a
19
1b
1c
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
26
00
00
Error code: 00
Starting... 2972
Results:
02
01
03
04
06
08
0a
09
0b
0c
0e
0d
0f
13
14
16
18
1a
19
1b
1c
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
26
00
00
Error code: 00
Starting... 2971
Results:
02
01
03
04
06
08
0a
09
0b
0c
0e
0d
0f
13
14
16
18
1a
19
1b
1c
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
26
00
00
Error code: 00
Starting... 2970
Results:
02
01
03
04
06
08
0a
09
0b
0c
0e
0d
0f
13
14
16
18
1a
19
1b
1c
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
26
00
00
Error code: 00
Starting... 2969
Results:
02
01
03
04
06
08
0a
09
0b
0c
0e
0d
13
14
16
18
5b
5c
1c
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
26
00
00
Error code: 00
Starting... 2968
Results:
02
01
03
04
06
08
0a
09
0b
0c
0e
0d
0f
13
14
16
18
1a
19
1b
1c
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
5e
1e
26
00
00
Error code: 00
SD card not valid or not inserted, doing a normal boot.
[pico] Changed state: WIIU_STATE_NEEDS_DEFUSE -> WIIU_STATE_NORMAL_BOOT
[pico] Changed state: WIIU_STATE_NORMAL_BOOT -> WIIU_CHECK_IF_POWERED_OFF
[pico] Changed state: WIIU_CHECK_IF_POWERED_OFF -> WIIU_STATE_POWERED_OFF

As far as the format, I used fat32 w/ 4096 byte allocation and no label. I did use windows to format the card to fat32 after using Win32DiskImager to flash the sd card with the boot1.img

 

[SDIO]

what happens if you just flash the boot1.img without doing anything else to the card?

 

[kitsune1324]

That's the log I just put in. The behavior between the two does not change at all. I have a 32gb sd card I could try but it's sdhc.

 

[SDIO]

nah a 32GB wont work. So looks like your card isn't compatible. Maybe insert/remove it a few times in case the contacts are oxidated, try a differen micro sd adapter and if nothing helps try another card.

What state is your wii u in?

 

[kitsune1324]

nah a 32GB wont work. So looks like your card isn't compatible. Maybe insert/remove it a few times in case the contacts are oxidated, try a differen micro sd adapter and if nothing helps try another card.

What state is your wii u in?

I'll try a different SD adapter, one that I know works. Still, it's odd that the cards are getting reformatted unless that's just part of the standard wiiu boot.

Regarding the state it's in, funny enough, you actually pointed me to de_fuse in the thread I started: https://gbatemp.net/threads/dead-system-memory.637749/#post-10221609.

TLDR: potential NAND failure (could boot the wii u and navigate, couldn't open browser or move 99% of saved game data), attempted an update which froze at 98%, now the wii u will only give a black screen when booting, no menus.

 

[SDIO]

maybe the card is broken and doesn't accept any writes. Did you test it without putting it in the wii u, just removing and reinserting into the pc?

 

[kitsune1324]

Confirmed both cards are working as expected in windows across multiple machines. I think the issue is when the wii u goes into its normal boot it reformats the card. When it doesn't the card stays in tact. I also tried another Micro SD - SD adapter (known good) and am experiencing the same behavior as above.

 

[SDIO]

the wii u doesn't format sd cards. There must be something else going on. Can you test the cards with h2wtest?

 

[kitsune1324]

Micro SD's were bad, don't cheap out with "cloudisk". I picked up a sandisk which h2testw tested without issue.

Good news: It's now defused!! Now to figure out what to do. I'll post an update if/when I unbrick it or have questions!

Post automatically merged: Aug 17, 2023

Looks like I ran into a stop already: Trying to boot, I get the purple LED and putty gives the message
[pico] Changed state: WIIU_STATE_NEEDS_DEFUSE -> WIIU_STATE_DEFUSED
[pico] Changed state: WIIU_STATE_DEFUSED -> WIIU_STATE_MONITORING

After that there is no additional info written out to PUTTY and the LED will turn to a flashing orange after a minute or two, again, nothing written out to PUTTY.

TO confirm, my file structure on the SD card looks like
├── fw.img
└── wiiu
....└── ios_plugins
....└── wafel_core.ipx

I checked the SD card and have no logs, I have also tried booting the wii u without the SD card and without the 3.3v (pico) and nothing's changed (as expected?).

What am I missing here?