Hardware/Testpoints

General

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

EXI0

TP100 - MOSI (Device in, Wii U out. Next to 176.)
TP101 - CLK
TP102 - CS
TP176 - MISO (Device out, Wii U in)

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

TP1 - wire goes all the way down near RTC? Also connects to SoC.
TP2 - near disk drive
TP3 - near disk drive
TP4 - near disk drive
TP5 - near disk drive
TP6 - To video chip and SoC
TP8 - U13 pin4
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.
TP10 - To video chip (and elsewhere?)
TP11 - Direct to SoC, no other connections.
TP12 - Direct to SoC, no other connections.
TP13 - Direct to SoC, no other connections.
TP14 - Direct to SoC, no other connections.
TP15 - Connects to SMC
TP16 - Connects to SMC
TP18 - near disk drive
TP19 - near disk drive
TP20 - Direct to SoC, no other connections.
TP31 - Composite related?
TP32 - Composite related?
TP33 - Composite related?
TP34 - Connects to RAM module?
TP35 - Connects to RAM module?
TP36 - Connects to RAM module?
TP37 - Connects to SMC
TP38 - Connects to SMC
TP39 - Connects to SMC
TP56 - Direct to SoC, no other connections.
TP57 - Direct to SoC, no other connections.
TP58 - Connects to RAM module?
TP59 - Connects to RAM module?
TP60 - Connects to RAM module?
TP61 - Connects to RAM module?
TP62 - Connects to RAM module?
TP64 - To U1014 (comparator?) pin12
TP65 - TP2003
TP66 - TP2000
TP67 - to front faceplate
TP68 - to front faceplate
TP69 - Direct to SoC, no other connections.
TP70 - TP2002
TP73 - backup battery 3v3?
TP76 - near disk drive
TP83 - Direct to video chip.
TP84 - To HDMI connector?
TP86 - Direct to SoC, no other connections. Lots of capacitors? Reference voltage?
TP87 - Direct to SoC, no other connections. Lots of capacitors? Reference voltage?
TP88 - backup battery related
TP95 - front USB 5V enable?
TP99 - Direct to DRH, no other connections.
TP109 - USB 5V enable?
TP110 - Wire goes past video chip away from SoC.
TP111 - To HDMI connector?
TP114 - near disk drive
TP115 - 12V DC plug positive?
TP116 - 12V DC plug positive?
TP117 - 12V DC plug negative?
TP118 - 12V DC plug negative?
TP120 - ??? power rail
TP122 - ??? power rail
TP123 - ??? power rail
TP125 - ARM/IOP PGOOD
TP126 - ARM/IOP LV5065 TD1/TD2?
TP127 - ARM/IOP power rail?
TP128 - ARM/IOP GND
TP129 - ??? power rail
TP130 - ??? GND
TP132 - to comparators?
TP136 - ??? power rail
TP139 - ??? power rail
TP141 - Connected to RTC. Pulled up by Q1080?
TP142 - ??? power rail
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?
TP151 - Connected to transistor output, goes to SoC
TP155 - Connected to SMC, and SoC(?)
TP160 - GND
TP161 - GND
TP163 - GND
TP164 - GND
TP165 - GND
TP166 - GND
TP166 - ??? power rail
TP169 - GND
TP170 - Eject Button (active low/pullup, pressed=0.0v, not pressed=3.3v)
TP173 - 5GHz Wifi idk
TP174 - 2.4GHz Wifi idk
TP179 - Direct to DRH, pullup resistor?
TP187 - LV5064 pin21 (and more?)
TP191 - Direct to SoC, no other connections.
TP1000 - Direct to SoC, no other connections.
TP1001 - Direct to SoC, no other connections.
TP1002 - Direct to SoC, no other connections.
TP1003 - Direct to SoC, no other connections.
TP1004 - LV5064 pin10, temp sensing? direct to SoC
TP1005 - LV5064 pin11, temp sensing? direct to SoC
TP1006 - LV5064 pin12, temp sensing? direct to SoC
TP1007 - LV5064 pin13, temp sensing? direct to SoC
TP1008 - LV5064 pin14, temp sensing? direct to SoC
TP1010 - LV5064 pin9, temp sensing? direct to SoC
TP2000 - To SMC
TP2001 - To faceplate
TP2002 - Power Button (active low/pullup, pressed=0.0v, not pressed=3.3v)
TP2003 - To some transistor gate?
TP2004 - GND
TP4000 - Direct to SoC, no other connections.
TP4001 - Direct to SoC, no other connections.
TP4003 - Direct to SoC, no other connections.