Hardware/Testpoints

General

The Wii U motherboard exposes several test points, primarily on the bottom of the motherboard (CPU heatsink facing down).

EXI0

• TP101 - CLK
• TP176 - MISO (Device out, Wii U in)
• Test point between TP100 and TP176 - MOSI (Device in, Wii U out)

DEBUG

These pins are set to various 8-bit values to indicate the current stage of boot0.

• TP50 - DEBUG0
• TP51 - DEBUG1
• TP52 - DEBUG2
• TP53 - DEBUG3
• TP55 - DEBUG4
• TP54 - DEBUG5
• TP48 - DEBUG6
• TP49 - DEBUG7

Misc/Unk

• TP9 - Fake Power Button (active low/pullup, pressed=0.0v, not pressed=3.3v), connected to SMC and RTC. Eject button will also pulse this low.
• TP70 - Power Button (active low/pullup, pressed=0.0v, not pressed=3.3v)
• TP102 - Not EXI0?
• TP127 - ARM/IOP power rail?
• TP141 - Connected to RTC. Pulled up by Q1080?
• TP144 - Reset? Or functions like one when pulled down by a 3.3Kohm resistor.
• TP145 - Connection between RTC and SMC, weirdly sensitive to measurement (power LED reverts to red, but SoC continues running)
• TP147 - Connected to RTC and pin4 of U1041 (Comparator in?)
• TP148 - Connected to RTC and Q1093 gate. Makes its way to U1041 Pin13 (Comparator ?)
• TP149 - Connected to LV5066 pin2 (EN) and RTC. Regulators enable? Pulldown resistor?
• TP170 - Eject Button (active low/pullup, pressed=0.0v, not pressed=3.3v)
• TP1005 - LV5064 SMBus SDAI, also connected to SoC
• TP1006 - LV5064 SMBus SDAO, also connected to SoC
• TP1007 - LV5064 SMBus SCL, also connected to SoC
• TP1008 - LV5064 SMBus SMBA (alert), also connected to SoC