Unbrick of the death !

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If your WDTV reboots or restarts blocked, it is because your flash failed.
But there is a solution (that doesn’t work in all cases but will allow you to take control via JTAG) !

To force the flash, you will have to invalidate the primary file system !

You must remove the motherboard from the case. Then desolder the metal shield.
You must use a high power soldering iron if the heat is absorbed by the metal plate. Personally, I use a mini torch.

Then you have to solder a wire on a pin of the “Chip Enable” flash chipset. (Use a low power iron soldering now).

The wire must be long enough to go around the mainboard and touch the VCC jtag pin.

Now it should boot without touching for now. This is what the JTAG displays :

Reading NAND CS0, addr 0x01280000, size 0x00000800 to 0xb5ffbfc0
Reading NAND CS0, addr 0x01280800, size 0x003aac00 to 0xb5ffc7c0

There are tree reading operations.
Reading NAND CS0, addr 0x00d80000, size 0x00000800 to 0xb63fbfe0
Reading NAND CS0, addr 0x00d80800, size 0x00022400 to 0xb63fc7e0
Reading zboot
....
Reading NAND CS0, addr 0x01280000, size 0x00000800 to 0xb5ffbfc0
Reading NAND CS0, addr 0x01280800, size 0x003aac00 to 0xb5ffc7c0
Reading primary file system
....
Reading NAND CS0, addr 0x00780000, size 0x00000800 to 0x01840000
Reading NAND CS0, addr 0x00780800, size 0x00402400 to 0x01840800
Reading secondary file system

The readings two and tree only take tree second. You must then operate during the second reading, then make the wire touch the VCC for less than a half of a second. The primary filesystem MD5 will be invalid. The WDTV will then directly boot to the secondary file system but will only partially execute the init script.

You should now get the jtag bash. If this is not the case, it’s very bad !
Insert the USB drive with the homebrew and run the command ./init upgrade.
Wait, reboot and flash.

I performed this only two times, but both flawlessly.

Good luck !

9 réflexions au sujet de « Unbrick of the death ! »

  1. Thank you for the Jtag procedure.

    I was experiencing the reboot loop at the WD TV Live logo on my gen3 streaming media player. I hooked up my USB to TTL cable and looked at the output in putty.

    See the output here: https://pastebin.com/m8PEKSJp

    I was then prompted at the end of the putty readout with this:

    “Sigma Designs SMP863x development environment (based on the buildroot project)
    (none) login: ”

    So I logged in with root (no password) and ran the “./init upgrade” command

    I downloaded and extracted the WD Firmware Ver. 2.01.86 to a usb storage device but did not plug it into the WD TV Live streaming media player.

    See the current putty read out after the ./init upgrade command here https://pastebin.com/snNaPr3t

    If I plug in the USB drive with the firmware file this is the putty output

    usb 2-1: new high speed USB device using tangox-ehci-hcd-1 and address 2
    hub 2-0:1.0: Cannot enable port 1. Maybe the USB cable is bad?
    usb 2-1: new high speed USB device using tangox-ehci-hcd-1 and address 3
    usb 2-1: configuration #1 chosen from 1 choice
    scsi0 : SCSI emulation for USB Mass Storage devices
    usb-storage: device found at 3
    scsi 0:0:0:0: Direct-Access Kingston DataTraveler 2.0 PMAP PQ: 0 ANSI: 0 CCS
    sd 0:0:0:0: [sda] 7839744 512-byte hardware sectors (4014 MB)
    sd 0:0:0:0: [sda] Write Protect is off
    sd 0:0:0:0: [sda] Mode Sense: 23 00 00 00
    sd 0:0:0:0: [sda] Assuming drive cache: write through
    sd 0:0:0:0: [sda] 7839744 512-byte hardware sectors (4014 MB)
    sd 0:0:0:0: [sda] Write Protect is off
    sd 0:0:0:0: [sda] Mode Sense: 23 00 00 00
    sd 0:0:0:0: [sda] Assuming drive cache: write through
    sda: sda1
    sd 0:0:0:0: [sda] Attached SCSI removable disk
    sd 0:0:0:0: Attached scsi generic sg0 type 0
    usb-storage: device scan complete
    /dev/sda sleep 1 seconds…
    /dev/sda1 sleep 4 seconds…
    /dev/sda sleep 1 seconds… done
    mount /dev/sda on /mnt/sda with vfat failed1: 255
    mount /dev/sda on /mnt/sda with msdos failed2: 255
    mount /dev/sda on /mnt/sda with ntfs failed3: 255
    mount /dev/sda on /mnt/sda with ext2 failed4: 255
    mount /dev/sda on /mnt/sda with hfs failed6: 255
    mount /dev/sda failed..
    find_firmware on /dev/sda done..
    /dev/sda1 sleep 4 seconds… done
    mounted /dev/ sda1 ok..
    enter loop 2
    enter loop 3
    enter loop 4
    enter loop 5
    enter loop 6
    enter loop 7
    enter loop 8
    enter loop 9
    enter loop 10
    enter loop 11
    Found romfs.bin…
    … … …
    Mount APP firmware to /mnt/firmware..
    losetup -o /dev/loop0 , ret=0
    UDF-fs: No VRS found
    yaffs: dev is 7340032 name is “loop0″ ro
    yaffs: passed flags “”
    yaffs: Attempting MTD mount of 7.0,”loop0″
    yaffs: dev is 7340032 name is “loop0″ ro
    yaffs: passed flags “”
    yaffs: Attempting MTD mount of 7.0,”loop0″
    ufsd: default nls iso8859-1
    Mount RET = 255
    Fail to mount APP firmware to /mnt/firmware..
    losetup -d /dev/loop0
    umount /mnt/sda1
    find_firmware on /dev/sda1 done..

    I’m not sure it is updating. Any help would be great.

    Cheers and thanks in advance

  4. Hi,
    That’s an awesome job! I’m actually having the same problem but on wdtv live hub, and I think I found the “Chip Enable” Flash Chipset..
    So will it work on my wdtv live hub?

    • The WDTV Live Hub is very similar to the WDTV Live Streaming. In addition to the “Chip Enable”, you need a JTag to monitor and activate the “Chip Enable” at the right time.
      If your WDTV Live Hub has an official firmware, it will force the flash with an official firmware. If you built your own homebrew but your WDTV unbootable because of a defect in your homebrew, you need a homebrew built from Western’s source without modification. Otherwise you may fall on the same problem.
      You can send me the JTag’s logs if you have difficulty finding the right sequence of switches. I try to analyze the cause of the failure.

      good luck

  5. Hello! I put the boot nayaal, he copied, issued a request for the type of installed firmware. At this time otlyuchili electricity. Now, any firmware does not want to put all the time the inscription: “warning the media player was modified aftermarket and is running unofficial firmware that is not supported by western digital”. In YAMON I get, but what to do next? Please help.

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