eMMC / Flash

The flash chip is accessed via an eMMC controller.

Filesystem

See XBFS.

Flash chips

  • SK Hynix H26M42003GMR 8GB eMMC NAND Flash (Xbox One)
  • Toshiba THGBMFG6C1LBAIL 8 GB eMMC NAND Flash (Xbox One S)

Reading eMMC via hardware

Durango

Motherboard overview:

Mainboard top view

Mainboard bottom view

SD Card Connections:

SD Card pinout

Important:

For the x2 GND wires use 12 AWG. For the other connections use 28 AWG.

2 = CMD

3 = GND

5 = CLK

6 = GND

7 = DAT0

Enable SMC_RESET (VERY IMPORTANT TO DO THIS FIRST!!) Place a 200-300 Ohm resistor between J4E1.1 and TP4E1

Enabling SMC_RESET

Disconnect the SMC clock from the Southbridge by removing R4D2. Save the resistor as it is needed for the Xbox One to function. If you do lose it then a solder bridge should work as the value is 0 Ohms.

Disconnecting SMC clock

NAND logic runs on the 1.8v rail and readers try to use 3.3v which is most of them don't work with the Xbox One NAND.

Bridge a 700-800 Ohm resistor between Pin 1 of U3C3 and Ground. This should make an output 3v3 on the rail without damaging anything because the SMC is held in reset, so it won't try to power anything on.

Getting voltage to 3,3V

Directly underneath the NAND on the underside of the mobo are access points that will let you easily solder the CMD,DAT0 and CLK lines.

Everything works better when you hook everything up to the SD reader with everything turned off, then turn the Xbox One on and then plug in the SD reader to the PC.

GND solder points

eMMC communication points

Source: Team Xecuter / xpgamesaves

References

SK Hynix H26M42003GMR