[Wii U scene] A new modchip is being developed for the modification of the Wii U console

Everyone will be wondering if we really need it, the answer is yes and no, the Wii U console can already be modified via software, so why complicate our lives by installing a modchip?

While there is a coldboot boot1 vulnerability, isfshax , this leaves a lot to be desired and is unfortunately not useful for recovering consoles from an unknown state, as the NAND would be per-console encrypted based on an OTP key. 

Also, some  SEEPROM corruptions may cause consoles to never reach boot1, leading to an irreversible bricking of the console (at least without puncturing the SoC substrate).

From here starts the development of a new open source modchip by the developer shinyquagsire23 which allows to obtain the execution of boot1 by injecting a voltage problem shortly after the reset, before the console starts executing the code.

The de_Fuse modchip , this is its name, started on the Wii Mini console , at the time of the facts not yet hacked, born with the aim of executing the glitch on boot0.

Shortly after he discovered that the same technique could also be used on Wii U consoles , with the only disadvantage that the OTP dumps turned out to be impossible to dump, because they would be all 00while the driver for boot0 was limited to SDHC cards only.

Despite these small loopholes, the modchip could actually serve its purpose,  allowing a Wii U console to boot directly from the SD card, without having to rely on the internal eMMC chip to boot into the console.

This could really come in handy as many are complaining of crashes due to a faulty eMMC chip and now it’s possible to give gamers a way to boot from the SD card.

All the information reported by shinyquagsire23 are purely technical and would concern the eFuse, the OTP, the boot0, the boot1 and the SRAM of the console, therefore those interested in more in-depth and detailed information on the process can read it in the article written at this address .

The modchip is currently in its early stages of development and currently requires some sort of FPGA, but hasn’t been standardized in terms of schematics or parts, it is also thought to use an RP2040 microcontroller, the same one used on Switch consoles by the PicoFly modchip.

The cost of the different components should be around 25 to 35 dollars, if not less. This is instead the address for the project repository: https://github.com/shinyquagsire23/wii_u_modchip

Source: gbatemp.net