The iPhone Wiki is no longer updated. Visit this article on The Apple Wiki for current information. |
S5L8900
This is the Application Processor shared between the iPhone, iPod touch, and the iPhone 3G. Not much is known about it through official sources. According to saurik, this is an "arm1176jzf-s", if you're looking for manuals. This processor is not used in any of the newest devices, being replaced by the S5L8720, S5L8920, S5L8922, S5L8930, S5L8940, S5L8942 and S5L8945.
Contents
Firmware File Formats
Bootrom Exploits
Boot Chain
VROM (S5L8900)->LLB->iBoot->Kernel->System Software
One of the iPhoneLinux goals are to replace that Boot Chain after iBoot:
VROM (S5L8900)->OpeniBoot->Linux Kernel->X Server->Window Manager
Upgrade Process
Restore Mode
The common upgrade process chain is VROM->DFU Mode->WTF->iBoot->Kernel->Ramdisk->Restore Mode.
DFU Mode
To flash an older version of the iPhone software you have to let your phone reside in DFU Mode. In iTunes you have to press the option key (Mac) or the shift key (Windows) when pressing 'Restore' to be able to manually chose an IPSW.