How to check your iPhone’s Baseband and Bootloader

I am sure by now you are hearing the word “Bootloader” being thrown around allot, especially when it comes to upgrading and unlocking, and wondering what the hell it is.

“The iPhone is a small computer with two processors, some RAM and some eraseable FLASH for long-term storage (the 8GB of storage).

ARM Core: This is the processor used to run the Operating System (the OS), which is a scaled down version of MAC OS X. The job of the OS is as a general manager of the phone’s resources (RAM, FLASH, Baseband, etc…) , as well as overview the concurrent running of the phone’s applications.

Baseband: This is the processor that manages all the functions which need an antenna. The GSM phone, as well as the WiFi and bluetooth are all under the control of the baseband processor. The baseband processor has its own RAM and FLASH resources, separate from the ARM core resources. The baseband processor is a resource to the OS.

Boot Loader: This is a (normally) very small program in non-volatile memory (can be FLASH, often is un-eraseable) that ‘bootstraps’ a processor startup and calls the main (usually much larger) program. The boot loaderhas also the responsibility to provide a protocol for obtaining and storing an updated version of the main program. Normally, the boot loader changes very rarely, as there is no need to. It is the main program that gets upgraded, not the boot loader. Also, if something happens during the update of the main program, the boot loader will always be there to save you and restore the main program with a good one. However, when you update the boot loader, if anything bad happens, then you have no more boot loader, which means that the processor will not restart at all. A Brick.

Source = http://www.hackint0sh.org/forum/show…hone+internals

Now that you understand what the bootloader does, here is a easy way to check:

Add www.trejan.com/irepo to your installer sources and install Baseband Info, launch it on your phone and it will tell you all sorts of cool infor about your iPhone, and the most crucial, what bootloader you have, and if you will be able to software unlock your iPhone when the 1.1.3 software unlock comes out.

the following is taken from: http://george.zjlotto.com/

Various Baseband FLS/EEP Files 04Feb08 | 0

With the newly decrypted ramdisks, it’s now possible to use bbupdater to reflash the baseband (with bootloader 3.9) directly to any version (regardless it’s downgrading or upgrading) without first going to 03.14.08_G then upgrading with iTunes.

Thanks Zibri, Geohot, Dev Team and all the hard working people who made this possible!

For 04.03.13_G (1.1.3): ICE04.03.13_G.fls / ICE04.03.13_G.eep
For 04.02.13_G (1.1.2): ICE04.02.13_G.fls / ICE04.02.13_G.eep
For 04.01.13_G (1.1.1): ICE04.01.13_G.fls / ICE04.01.13_G.eep
For 03.14.08_G (1.0.2): ICE03.14.08_G.fls / ICE03.14.08_G.eep

How to Use These Files

Example #1

Upgrade modem from 04.01.13_G to 04.02.13_G without upgrading firmware, get the following files:

iEraserBBUpdaterSecpack040113ICE04.02.13_G.flsICE04.02.13_G.eep

Then take the usual steps to reflash the modem.

Example #2

Downgrade modem from 04.03.13_G (BL3.9) to 04.01.13_G, get these files:

iEraserBBUpdaterSecpack040313ICE04.01.13_G.flsICE04.01.13_G.eep

Secpacks |

• For baseband 03.14.08_G (Firmware 1.0.2)
• Baseband 03.14.08_G Secpack

• For baseband 04.01.13_G (Firmware 1.1.1)
• Baseband 04.01.13_G Secpack

• For baseband 04.02.13_G (Firmware 1.1.2)
• Baseband 04.02.13_G Secpack

• For baseband 04.03.13_G (Firmware 1.1.3)
• Baseband 04.03.13_G Secpack

This patch is included both in Natetrue’s 1.1.3 Soft-Upgrade as well as in Dev Team’s Jailbreak 1.1.3.

Original: 1.1.3 Original Lockdownd

Patched: 1.1.3 Lockdownd Patched