How to downgrade the Archos 5 firmware

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This page describes the process of downgrading the firmware on the Archos 5 or Archos 7 devices.

This procedure works for all current Archos firmwares, up to and including 1.7.17.

Step 1

First, boot your device into recovery mode:

  • Power down your device: press the Power button until you see the Shutting Down... message appear on the screen.
  • Power up in recovery mode: press Power+Volume Up and hold them until the recovery screen appear.
  • Select Repair Disk mode: press Volume Down and then Power to select.
  • Connect the USB cable to a computer.

Step 2

Second, mount the system partition:

user@computer:~$ sudo fdisk -l

Disk /dev/sdb: 120.0 GB, 120034123776 bytes
255 heads, 63 sectors/track, 14593 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0xf3a405dd

   Device Boot      Start         End      Blocks   Id  System
/dev/sdb1               1       14568   117017428+   c  W95 FAT32 (LBA)

The data partition (/dev/sdb1) is 14568 cylinders long and the whole disk is 14593 cylinders long. The system partition is located after the data partition in the last 25 cynlinders. At 8225280 bytes per cylinders, that means the system partition is 205632000 bytes (196 MB). This also means the first byte of the system partition is written at 14568×8225280=119825879040 bytes on the disk, and knowing it's an ext3 filesystem you can mount it with the following command:

sudo mkdir /media/disk
sudo mount -t ext3 -o offset=119825879040 /dev/sdb /media/disk

Now the offset can be different depending on the size of the disk, so do the maths for yourself.

Step 3

Third, to actually downgrade the firmware, grab a copy of the firmware version 1.6.54 (any firmware <=1.6.54 will do) and run this command:

aos-unpack firmware_archos5-7-1.6.54.aos

This command will create a folder containing many files. You will need to locate three files and copy them to the system partition of your device. Here's a copy of the files, in case you don't have aos-unpack compiled:

Now to make sure the changes took, don't forget to sync the disk before unmounting it.

sudo sync
sudo umount /media/disk

(make sure that the original firmware_archos5-7.aos file is in media/ARCHOS/)

It's done! Your firmware is downgraded... Err, almost. Your Archos is still using the same bootloader you had before, the only difference is that the rootfs (which contains the filesystem and all programs) is now at version 1.6.54. This means that you can install any firmware version >= 1.6.54 directly from the Tools > Settings > Firmware and Plug-ins menu (at this point, you can still only install original firmwares).

In order to have a proper firmware with the bootloader and the OS all at the same version, it is recommended that you install an original 1.6.54 firmware. But note that this is not necessary if you are installing a patched firmware, in which case you can skip directly to the page of interest, how to install a patched firmware.

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