release
dev builds
extras
themes manual
wiki
device status forums
mailing lists
IRC bugs
patches
dev guide



Search | Go
Wiki > Main > SansaFuzePlus > SansaFuzePlusRescue (r4)

This page summarize some information on rescue tools and procedures for the Sansa Fuze+ player.

DO NOT attempt this procedure without asking for some advise on IRC. This procedure is non trivial, it will require you to open your player and do unsafe operations. Most of the possible "brick" states of the Fuze+ can be recovered without this procedure and thus it should only be attempted when failure of the internal storage has been identified

Internal storage failure

Some early Fuze+ have suffered from an internal storage defect making them partly or completely unusable. While the internal storage cannot be recovered (as far as we know) , the following procedure will allow you to go on using rockbox on such device by launching it from a microSD card. It consists mostly in two steps:
  • modify the i2c eeprom (which is what the I.MX233 boots off) to boot frol the microSD instead if the eMMC.
  • correctly format a microSD card that is recognised as bootable by the device

This procedure will require that you build a custom version of the bootloader and rockbox. Indeed normal version will try to make use of the internal storage. The patches required can be found here: g#567

Modify the i2c eeprom's firmware on your device

Modifying the EEPROM is the tricky step. Indeed this this EEPROM is easily accessible from the i2c bus of the device but it is write protected by default. However the write protected pin is not heavily grounded which makes it possible to disable the protection on a temporary fashion. So the procedure will look like this:
  • tear you player appart
  • locate the eeprom
  • put your device in recovery mode
  • boot a special file
  • repeat until success: short the write protect pin, write the EEPROM, check for success

Format your mircoSD card to have both a bootloader and the usual partition

You need to create 2 partitions on the microSD card:

  • one for the bootloader (about 100 MB)
  • a second FAT32 partition to be used as common rockbox storage (that will recieve rockbox directory and your music files)

Linux:

You can use gparted to created those two partitions. The bootloader partition can be of any filesystem's type as we will reset it afterward (although setting some different filesystem from FAT32 can help you to identify it on the card.)

Then from a console as root launch fdisk on the microSD device:

fdisk /dev/sdX
where sdX is the name of the MicroSD? device (typically X is to be remplace by a letter, sdc for instance) Be sure to identify clearly that letter as a mistake can make some of your other partition unusable.

Type p to list all partition and identify the number of the future bootloader partition (it should be the one having the lowest number of blocks). Then enter t, then the number of the bootloader partition, then 53 as OnTrack? DM6 Aux3 filesystem. Finally enter w to write modification to the device.

Compile or get a rockbox bootloader and directory modified to run from the microSD

If you already know how to compile you can apply this patch and compile your own bootloader/directory: g#567

Otherwise you can get a precompiled bootloader here and a precompiled directory here

Note that the precompiled bootloader/directory might be old and/or buggy and thus is unsupported.

Copy the bootloader on the bootloader filesystem.

Linux:

You can copy the bootloader to microSD partition with the following command

dd if=firmware.sb bs=512 seek=4 of=/dev/sdX$
where in sdX$, X is the same letter as above and $ the number of the bootloader partition on the microSD

It isn't very clear if this step is necessary, but if you still cannot start the bootloader you can add one last command:

dd if=/dev/zero bs=512 count=4 of=/dev/sdX$
where sdX$ stand as above

-- JeanLouisBiasini - 16 Aug 2013
Edit | Attach | Print version | History: r5 < r4 < r3 < r2 | Backlinks | View wiki text | More topic actions...
r4 - 01 Dec 2013 - 10:24:04 - JeanLouisBiasini

Parents: SansaFuzePlus
Copyright by the contributing authors.