Whether you need to replace a dying hard drive, or are doing a mod chip, or just want to backup 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.

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 24C02 8-SOIC 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.