Whether you need to replace a dying hard drive, or are doing a mod chip, or just want to back up your EEPROM for future preservation, I will show you below how to dump your EEPROM.

The EEPROM varies from console revision, but in general it is 2kb organised in 256x8bit pages (so 32 pages, 256 / 8), such as AT24C02 (or any other 24C02 variant).

The EEPROM is located typically on the left side of the console near the debug connectors. If you check with a multimeter the debug header usually has the SCLK and SDAT pins on it so you can connect to there.

If you have a modded console, just run the Config Magic app to view the EEPROM data. This can be found on the Cerbios Installer or Hexen Installer discs also.

It is the Unique HDD Key 32 digit value you want, for example ec53d78f9107b5135b8f849be7033111.

There are many tutorials online of reading the EEPROM using PiPROM, ArduinoProm or similar. However I find a much easier method is to just remove the EEPROM off the console, connect it up to an XGEcu T48/56 or similar, and simply read it out.

Select Atmel AT24C02@SOIC8 as the chip and press Read.

Now you have the EEPROM bin file you want to read it so you can do things like lock a new hard drive to it with the specific key.

For that we use XboxEepromEditor. Open it up, then select File > Open and then select the bin file.

The useful info we usually want is the HDD Key.

This can be used to lock a new HDD to the console.

Now you have the EEPROM bin file, you can load it up in XboxEepromEditor and edit anything you like, then do File > Save As and then save out the new bin file.

The typical option is to change your HDD Key to 11111111111111111111111111111111. which is 32 digits of 1. This is the typical default value used when doing HDD swaps so you can always make new hard drives with all 1s and use them in any console with the same key.

Once you save out the new file, attach the EEPROM to the XGEcu T48/56 or similar.

Select Atmel AT24C02@SOIC8 as the chip and then press Load and select the new saved bin file.

Hit Program to flash the new binary to the EEPROM.