External Memory Unit
The original Xbox 360 models had the option of using proprietary memory cards, which connected to two unique ports on the front of the console. You could get them in 64 MB, 256 MB, and 512 MB sizes. Like the original Xbox's memory cards, they are just USB devices but operate with 3.3V logic. In fact, they can even be used on the original Xbox if you have a way to connect them to the system.
Models
- X801935-004
- X809156-003
- X811680-003
- X811680-002
Pinout
If you want to connect the memory unit to a PC, you will need to have a 3.3V voltage regulator, such as an AMS1117. Not having a voltage regulator may damage the memory unit if you plug it into a 5V host.
Console Port Pinout
The square pin next to 3.3V also acts as an extra ground header.
Internal Memory Unit
Many Xbox 360 motherboard revisions happen to have an unused header for an extra memory unit, which can be taken advantage of if you have soldering equipment. This page will document the locations of the memory unit header, along with a corresponding pinout to attach a female USB port. All Phat models also have two additional accessible USB lines.
Jasper/Tonasket also had the additional configuration of using "big block" 256/512 MB NANDs, which allowed for the ability for Xbox 360 Arcade models to have a small amount of built-in storage instead of relying on an external memory card.
It should be noted that the internal memory unit headers on the Falcon & Trinity operate at 3.3V, so the majority of USB drives will not work. To use a normal USB device on the internal memory unit headers, you have to get 5V from another source, like a nearby transistor. However, if you want to use a phat or Trinity memory unit on these headers, you will need to use the 3.3V line instead.
All Phat Models
Zephyr
CobaltPort
Falcon
Memport3_ArgonYeti
Memport3_Flash (J1E2)
To use this memory unit header on Falcon, you will also need to either populate two resistor spots with 0 ohm resistors, or bridge the resistor pads with some wire.
Jasper
This cannot be done on Tonasket, as the headers used for Dumbo are gone on that revision. In fact, the extra USB connections from the south bridge appear to not be accessible at all on that revision.
J2D3 Header
Trinity
Trinity consoles are unique, as the 4 GB Xbox 360 S consoles with the Trinity motherboard actually came with a 4 GB module attached to the internal header. HDD consoles usually didn't have the connector populated.
4 GB Memory Unit Models
If you want to connect the memory unit to a PC, you will need to have a 3.3V voltage regulator, such as an AMS1117. Not having a voltage regulator may damage the memory unit if you plug it into a 5V host.
X854803-002
40183 Rev D
The motherboard connector pinout of this is the same as the X854803-002, so you can just refer to its diagram.
J1D1 Header
Corona, Waitsburg, Stingray, & Winchester/Barracuda
On Corona and later, the unused header just acts as a normal USB port, including the fact that 5V is directly on the header as well. 3.3V can be obtained from the nearby interface for the eMMC, if that's desired for some reason.
J1D1 Header
MMC/eMMC
Unlike the Trinity's approach, the consoles configured as 4 GB with Corona and newer motherboards have the 4 GB memory soldered directly in-place of the SLC TSOP NAND used on previous motherboards.
More info on the 4 GB MMC/eMMC can be found on XenonLibrary.