Bricked Kindle Touch

[linuxuser]

Originally Posted by Crevecoeur

Hey, no need to belabor the point about not bothering yifanlu while he works on this. This is great news and certainly worth waiting for. In the meantime, I will continue working with serial port method as time permits.

Thank you both (yifanlu and geekmaster) for all the work you've put into this. My own frustration just stems from the fact that I am eager to get back to actually using my Kindle (I just wanted to change some fonts, and everything was almost perfect when it bricked!).

Crevecoeur, I have the same anxiety. Will have to wait a bit.

[linuxuser]

In DS_TTL-232RG_CABLES pdf file speaks of two different drivers:

- VIRTUAL COM PORT(libftd_sio)
- D2XX Direct Drivers(libftd2xx)

Does anyone know what should I use?

[Crevecoeur]

I used the virtual com drivers, and unless I'm mistaken, I think it is what most people would use for this purpose.

[geekmaster]

I successfully debricked my k4nt that had corrupted MMC including root partition and linux kernel and idme vars (serial number, MAC address, etc.). I was able to rewrite the MMC with a backup copy from my other k4nt, and then I rewrote the idme vars from original values I found in diagnostic log files.

I did not use the serial port. I only used the freescale mfgtool to download and run a patched copy of u-boot in the kindle RAM, to rewrite my idme "pcbsn" var so it could continue the boot process, and to switch my kindle to "fastboot" mode. I added forcing the pcbsn and fastboot mode to the u-boot source code in the amazon gpl source code for my kindle, then I compiled it using the latest debian arm-cross compiler installed with apt-get on my ubuntu host PC. Then I used yifanlu's fastboot tool to rewrite my backup images onto my kindle MMC. I extracted the main and diag linux kernels from a backup image of the first 32MB of /dev/mmcblk0 on my other (good) k4nt, using a hex editor. The length of the kernels is stored in a flash header at the beginning of each kernel in the backup image.

The only caveat was that my kindle could not be registered until a tech specialist at amazon manually associated my serial number and MAC address, which were not listed in their system as belonging together. I got them from an XML log file of diagnostic results originally from that damaged kindle, so either the report was not correct, or somehow trying to login with damaged idme confused my kindle info at amazon.

A side effect of amazon reassociating my kindle serial number with its MAC address is that registering made my "Special Offer" k4 into a non-SO k4. The ads disappeared after registering, and they have not come back.

Anyway, I have a special u-boot.bin that will switch the kindle to fastboot mode, where you can erase the /var/local partition in case it got filled up, then use fastboot to switch to main or diag mode, where you can do more repair work. When the kindle boots, it automatically reformats and builds a new mmcblk0p3 (/var/local) if it is erased, and it will also reformat and rebuild the USB Drive if it is erased. I erased both user partitions on my damaged k4nt from fastboot, when I rewrote the kernels and main and diag partitions.

On the k4nt, from diags, you can start SSH. On the touch, you can push a netcat reverse shell from the ixtab jailbreak runme.sh script. A reverse shell lets you run commands on your kindle just like SSH or telnet (but with no command prompt).

[Poetcop]

Thanks for writing this Geekmaster! I'm happy because I feel like I'm close to getting my Kindle back - maybe it is simply a matter of learning to use the freescale tool and running it with your u-boot.bin, and then erasing the /var/local partition, which would then regenerate (you're pretty sure about that right?). That would be great! I remember there being quite a few directories in /var/local, but according to the wiki it only holds preferences and things - it sounds like I might get my /mnt/us back, and maybe not even have to rerun the jailbreak.

[Poetcop]

Ignore this - I just saw your message in the other thread!

[geekmaster]

I am writing a simple tool that uses my fix, which minimizes the technical expertise needed to do it the way I did. Read more here:
https://www.mobileread.com/forums/sho...48&postcount=4

[linuxuser]

Crevecoeur, finally configure the linux module for ftdi chipset was very easy and support hotplug mounting device on /dev/ttyUSB0 file.

The next link explains as do: http://www.gentoo-wiki.info/Usb-uirt ("Kernel config changes section")

[linuxuser]

A question for those who managed to connect to the Kindle Touch:
In the electronics store I was told that for solder a wire to each terminal serial port is necessary to use a welder work at an special temperature.

I can you use a regular soldering iron or should to be special?
They remember that power was his soldier?
In what ways soldered the wires?

Thanks.

[geekmaster]

Originally Posted by linuxuser

A question for those who managed to connect to the Kindle Touch:
In the electronics store I was told that for solder a wire to each terminal serial port is necessary to use a welder work at an special temperature.

I can you use a regular soldering iron or should to be special?
They remember that power was his soldier?
In what ways soldered the wires?

Thanks.

For soldering to circuit boards, I use a temperature controlled soldering stations the runs at 600F, but for most other things (like connectors) I use 700F.

If you are new to soldering, do NOT use acid-core solder intending for plumbing applications! The acid in the solder flux will damage sensitive electronic components.

You must use rosin-core solder. Back before I could afford a soldering workstation, I used an inexpensive soldering iron connected to an ordinary incandescent light dimmer, turning it up only as much as I needed to melt the solder and do the job.

Too much heat will lift small traces away from the circuit board. It is better to be a little hot and get done quickly, than not enough heat applied for too much time, though.

For the kindles, it helps to have a very sharp pointed tip on the soldering iron (not a chisel tip).