Information gathered from iaudio X5 OF disassembly

Preloader

General Info

This part of firmware resides from 0x00000000 to 0x00010000 and never changes. It is a single-threaded program that handles the following tasks:

1. Device initialization.
2. USB HDD mode.
3. Adapter/USB charge mode.
4. Firmware upgrade.
5. Executing the actual firmware (i.e., jmp 0x10000).

To be continued...

Firmware

General Info

This part of firmware resides from 0x00010000 to ~0x019D0000 and can be upgraded.

It has two parts:

• the first is composed of ~18 data and/or code segments, most of which are cached to IRAM/DRAM.
• the second contains read-only data (images, remote images, text strings, ...) and begins at 0x01700000. H3Mod? changes things here.

To be continued...