NAND

Flash memory

File:Hynix flash rom.jpg Hynix HY27US08281A flash ROM device.It is believed the flash memory stores the Dash and other "Upgradeable" pieces of 360 Software.

The HYNIX HY27US08281A series is a 16Mx8bit with spare 4M bit capacity.

Datasheet of it: http://www.hynix.com/datasheet/pdf/flash/HY27US(08_16)281A%20Series(Rev0.6).pdf

SMT socket that should work if you choose to remove yours: http://www.emulation.com/cgi-cfm/insert_quantity.cfm?part_number=S%2DTSO%2DSM%2D048%2DA,

Attached to southbridge

Reading and Writing

The Flash can be written or read using a number of methods. If you have the old shader hack running the easiest is using lflash. You can also wire lpt directly to the flash using the diagram below.

http://img19.imageshack.us/img19/5198/wiringforxenondiagram.jpg

Once wired you can read or write to the chip using software such as NandPro.

Sectors

•1 copyright notice, zeros, unencrypted numbers

•2 encrypted data

@2MB filesystem, unencrypted, but content encrypted, config not

Small flash chip close to CPU

Some 360's also have a small flash chip near the CPU, as seen in these pictures:

•1stgame article (a developer unit) http://xbox360.1stgame.nl/13.html

•informit.com article http://www.informit.com/content/images/art_fogie_xbox360/elementLinks/fogie_fig09.jpg

•independent photo http://images.batlogic.com/albums/c60/mmattsson/xbox360/PDR_0033.jpg

•Anandtech article http://images.anandtech.com/reviews/system/microsoft/xbox360/mb.jpg

Not all boxes do have this chip. It does not seem to be core/premium related.

Here is a picture of a premium box without the chip:

•[1]

Here is a high-res picture of a premium box with the chip:

•[2]

As discussed in this article on the xboxhacker.net forums, this appears to be a Atmel 25020 EEPROM. The chip from the xbox360.1stgame.nl article reads:

ATMEL524
25020AN
SU18

Datasheet can be found here:

•http://www.atmel.com/dyn/resources/prod_documents/doc3348.pdf This chip is a low power 2048 bit serial EEPROM according to the datasheet.

•If the small chip near the cpu is removed the xbox will boot up and function just fine [Darkmoon 360 experiments]

•According to IBM the CPU has "an interface for a serial EEPROM in case patch logic configuration was needed during bring-up".

Small flash chip on front panel

There is another Atmel chip on the front panel:

File:Atmel2.jpg

Atmel 528 serial EEPROM.This chip reads:

ATMEL528
24C04N
SU18

Datasheet can be found here:

•http://www.atmel.com/dyn/resources/prod_documents/doc0180.pdf This chip is a low power 4096 bit serial EEPROM according to the datasheet.