Clara Bricked Clara HD after update?

[poplin]

Hi there!

After doing a regular update to my Clara HD I found the blinking 3 white dots over the black screen. After 30 min of waiting, nothing changed. Then I rebooted it.

It went into the "restoring" black screen but after 2 min everything stopped moving and now, not even holding the power button for one minute, I can go out of this screen.

Is this device irreversibly dead??

I've read that it is possible to install an image into the microSD and that should recover the device, but in that case, where and how can I get that image?

Thanks in advance for your help!!!

[Semwize]

Have you tried reset?

Manual reset your Kobo Clara HD

[poplin]

Thanks Semwize. Yes I've already tried but nothing changes. The reader continue stuck in the black "restoring" screen.

[Uschiekid]

Have you tried charging for a good long time (24 hours) and then resetting?

[davidfor]

Originally Posted by poplin

Thanks Semwize. Yes I've already tried but nothing changes. The reader continue stuck in the black "restoring" screen.

Try again, but, for step 2, hold the power button down for about 20 seconds. This will ensure the device is off before the next steps.

And charging the device for a while is also important. It is likely with the problems that it has run down the battery.

If that doesn't help, I have sent a PM with a link to the image. You can use Memory Upgrade Mod Guide as a guide for how to use the image.

[poplin]

Thanks everyone for your help!

So far nothing have changed. After charging around 12h I've tried the reset propose by Semwize and also holding 20s (as suggested by davidfor). Nothing changed. (FYI, holding the button 5s the led goes off and holding it 2 seconds light up blinking once)

I've burnt the new image (thanks davidfor) into the microSD (using dd command, i'm on a linux machine). Still stuck in the same initial black restoring screen. The reader does not seem to be either booting... or at least is not communicating with the screen

Running out of ideas, I'm thinking of unplugging the battery for a while to check if something changes

Any other advice? Thanks in advance!

[Semwize]

Try replacing the sd card with another one (8-32 GB). Not the fact that it will help, since you recorded the image without errors and most likely your sd card is working properly, but as an option ...

[poplin]

You nailed it!

Originally Posted by Semwize

Try replacing the sd card with another one (8-32 GB). Not the fact that it will help, since you recorded the image without errors and most likely your sd card is working properly, but as an option ...

The misleading and weird fact was that dd command did not ever show any error and finished normally (a bit too fast: 10 min compared to 1 hour for a good transfer). I realized that something was not going good after deleting all partitions in the sd card (fdisk), and checking that the following "successful" dd transfer was not rebuilding any partition...

So I've changed microSD and everything is back to normal now. Thanks again to you guys that helped me solving this!

For the sake of curiosity: I've seen that some people tested microSD up to 128Gb, but do you know which is the fastest that Clara HD could accept and if this speed would make any difference in usage?

[Semwize]

Originally Posted by poplin

For the sake of curiosity: I've seen that some people tested microSD up to 128Gb, but do you know which is the fastest that Clara HD could accept and if this speed would make any difference in usage?

I put 256 GB for the test, I do not recommend doing this, absolutely not necessary. My 1500 books (with pictures) are only 1.2 GB

So the optimal card size, in my opinion, is 32 GB. If you are not into comics.

The battery can still be increased, set at 2000mAh. If you are addicted to the upgrade.

[DNSB]

Originally Posted by poplin

For the sake of curiosity: I've seen that some people tested microSD up to 128Gb, but do you know which is the fastest that Clara HD could accept and if this speed would make any difference in usage?

What I've found most important is the small block transfer speeds. While quite a few uSD cards are optimized for recording video streams, my Kobo ereaders use a lot of small block reads and writes. Over the years SanDisk and Samsung seem to have the best results in that area. I use CrystalDiskMark for these tests. See this message and this message for some images of the output.

[Semwize]

Originally Posted by DNSB

Over the years SanDisk and Samsung seem to have the best results in that area. I use CrystalDiskMark for these tests. See this message and this message for some images of the output.

The tests are certainly great, but ...

I've tried both Samsung (currently installed Samsung EVO Plus) and Sandisk Extreme pro, and other cards. And there are no visual differences in the speed of the book. Unless in the speed of transferring books from a computer (but this is not important for most, since not many people transfer 1000 books each, right?).

I to the fact that I would not bother with the speeds, I did not see any noticeable and tangible improvements when changing cards. Excluding the transfer rate to and from the computer. And I did not see that wrote about such improvements. Rare exceptions can be explained by the fact that the stock card was originally defective, this happens.

[DNSB]

Originally Posted by Semwize

The tests are certainly great, but ...

I've tried both Samsung (currently installed Samsung EVO Plus) and Sandisk Extreme pro, and other cards. And there are no visual differences in the speed of the book. Unless in the speed of transferring books from a computer (but this is not important for most, since not many people transfer 1000 books each, right?).

I to the fact that I would not bother with the speeds, I did not see any noticeable and tangible improvements when changing maps. Excluding the transfer rate to and from the computer. And I did not see that wrote about such improvements. Rare exceptions can be explained by the fact that the stock card was originally defective, this happens.

I would have to disagree since I do not consider reading as being a good speed test given that virtually any setup can render pages faster than you can read them. What I did find was that operations such as timing importing 100 books, doing a database vacuum, doing a database backup and most other file operations were affected by the small block read/write speeds.

Please note that many high speed cards suck at small block operations since the blocks are smaller than the block size used internally by the uSD card and the firmware is optimized for handling video streams.

[Semwize]

Originally Posted by DNSB

I would have to disagree since I do not consider reading as being a good speed test given that virtually any setup can render pages faster than you can read them. What I did find was that operations such as timing importing 100 books, doing a database vacuum, doing a database backup and most other file operations were affected by the small block read/write speeds.

Please note that many high speed cards suck at small block operations since the blocks are smaller than the block size used internally by the uSD card and the firmware is optimized for handling video streams.

What exactly do you disagree with? I wrote about import / export of books, but how many users operate 100/1000 books at a time? Or are optimizing sqlite? So all these speeds are not really needed 99% of users ...

[DNSB]

Originally Posted by Semwize

What exactly do you disagree with? I wrote about import / export of books, but how many users operate 100/1000 books at a time? Or are optimizing sqlite? So all these speeds are not really needed 99% of users ...

The differences aren't that noticeable while reading. Since I do seem to have a habit of doing semi-regular factory resets, I fairly often transfer large blocks of books at one time. Other operations such as connecting to calibre and having it read the list of books from the device, backing up the database, updating metadata, etc. are also areas where the speed difference is noticeable.

Hence for me, choosing a uSD card that will speed up those operations is a worthwhile task and that is where we disagree.

[Semwize]

Originally Posted by DNSB

Since I do seem to have a habit of doing semi-regular factory resets, I fairly often transfer large blocks of books at one time.

Well, I transfer 1000+ books when experiments with firmware end up with a general reset to factory settings. But you and I are more likely an exception than a rule, and therefore it is wrong to set this as an example.

Correctly indicate - if you have a large database of books and you often copy it to / from the device, then yes - you can think about a faster card. Otherwise, you will not see the difference.