I’ve successfully reverse engineered the AOS1 file format. This means I can load any firmware on the Gmini 402 (or any device which uses the format) from an update file (*.AOS).
In a few weeks, I’ll release an utility allowing to load any firmware from an AOS update file, without flashing the device. This means it’ll be possible to temporarily use firmware 1.5.12 on a Gmini 402 1.3.11, and after a reboot, come back automatically to 1.3.11. This is useful for using USB Host mode with some cameras (like Canon ones) which were not detected by 1.3.11, and still use the 1.3.11 exploit to load mediOS and apps. Here is a piece of changelog of firmware 1.5.10:
USB Host: Cameras with proprietary protocols are detected and users are advised to switch it to a PTP or MSC protocol (notably Canon cameras)
Of course, temporarily loading a firmware was already possible, but releasing an utility to do so wasn’t, because it implied releasing copyrighted code from Archos. The utility I’ll release uses the AOS files provided by Archos, so there’s no copyright problem anymore.
Along with releasing the utility, I’ll detail the AOS1 file format.
The bootloader I aim to release will include this utility, to allow to boot on any firmware and mediOS and apps.