Baseband Firmware

The main instruction set of the baseband. You can get these files from  on the corresponding firmware's restore ramdisk or from an IPSW under.

The baseband version that comes with each iPhone firmware is listed on the firmware page and also on the X-Gold 608 article for the iPhone 3G/iPhone 3GS.

Baseband firmware files have been codenamed Trek, ICE, and MAV.

File Structure
The  file format is a ZIP archive containing ,  , and multiple firmware files. In the past, these were EEP and FLS files, the external EEPROM and firmware, respectively. In modern iOS versions, these are  files.

For example, the iPhone 4 has a single baseband firmware file. The 4.0 baseband firmware filename is  and contains contains four baseband firmware files.

Info.plist
The main identifying document for a given Baseband firmware is its. This PList contains the Build, ChipID, RestoreSBLVersion, SBLVersion, and Baseband Version of the firmware.

Other Links
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