Kobo H2O: Need SD Image

[frostschutz]

An approximation of where to expect glue. If you have to open it, I think it's best to start from the top left or top right corner, and not from the bottom since there's more glue and more sensitive bits down there (LED, light layer). Maybe warming it up a little would also help to soften the glue, I don't know. It was rather cold when I tried it and it did not come off easily.

As for the exact position of the SD card... the top left corner of the SD card is 18mm from the top and 28mm from the left, so it's pretty much aligned to the power button, which is 11mm-28mm from the left, so the SD card starts where the power button ends. And the SD card ends where the Kobo logo starts (on the X axis). It does not actually reach into the Kobo logo as the illustration makes it appear, the scale is quite inaccurate, sorry...

[mementomori]

Originally Posted by JSWolf

If you are going to go to the bother of opening the H2O, please use a good camera.So please redo the photos if at all possible. The ones posted are just too fuzzy to be of any use.

Why the heck to people do things like this just to take awful photos with a lousy cell phone?

Buy me a good camera and I will take it for you sir :P

Originally Posted by JSWolf

Please get a GOOD camera and retake the photos. Why do photos like this have to be poorly taken?

No cameras were involved while capturing this image.

(Does anyone have suggestions on producing a cleaner scan? When looking at the full resolution image, it looks like the board was vibrating. Or is it just a product of the quality of the scanner, since my old scanner definitely produced better results.)

[frostschutz]

Originally Posted by BWinmill

(Does anyone have suggestions on producing a cleaner scan?)

You'd need a CCD scanner; nowadays CIS is more common (particularly with all-in-one printers) but it lacks any kind of depth perception so you get blurry results when scanning objects such as this.

If you can get an old Epson 1260 (or whatever) from Ebay, around $10 if you are lucky... that's what I used to make scans of the iriver Story HD which turned out fine, if a bit too dark... but I don't have that device anymore so...

Originally Posted by frostschutz

You'd need a CCD scanner; nowadays CIS is more common (particularly with all-in-one printers) but it lacks any kind of depth perception so you get blurry results when scanning objects such as this.

Now that I know what to look for, that is definitely the cause. Thank-you.

[JSWolf]

Originally Posted by BWinmill

No cameras were involved while capturing this image.

(Does anyone have suggestions on producing a cleaner scan? When looking at the full resolution image, it looks like the board was vibrating. Or is it just a product of the quality of the scanner, since my old scanner definitely produced better results.)

You DO NOT scan it. You use a good digital camera to take a good photo. It's not hard to do. Why does it seem so hard for some?

[davidfor]

Originally Posted by JSWolf

You DO NOT scan it. You use a good digital camera to take a good photo. It's not hard to do. Why does it seem so hard for some?

Jon: Stop the rant. It probably means they don't own a "good digital camera". They used the tools at hand.

[frostschutz]

Recovering brick _without_ full SD image for the H2O:

Assuming only the system/data partition is bricked, but u-boot and recovery partition still intact, you should be able to force a factory reset, by extracting /etc/u-boot/mx50-ntx/u-boot.recovery out of the firmware update KoboRoot.tgz and putting it on the card in the right place.

dd if=kobo-update-3.12.0.tgz/etc/u-boot/mx50-ntx/u-boot.recovery of=/dev/sdcard bs=128k count=1 seek=6

When you put the card back into the device it should start up with the factory reset screen and, with some luck, unbrick from there. If it fails, you're back to needing the full SD image for recovery.

[davidfor]

If the recovery partition is still intact, would it be better to use the u-boot.recovery file that is on the recovery partition? That has the advantage that it should mean it matches the rest of the files used in the recovery and means you don't need to download the firmware package before trying this.

Originally Posted by davidfor

Jon: Stop the rant. It probably means they don't own a "good digital camera". They used the tools at hand.

I do have a decent digital camera but it is a fair bit easier to use a scanner. It's simply a matter of placing the board on the scanner bed and letting the software do the work. There's no need to worry about the lighting, stability, or distortion (because it is placed at an angle in 3-space instead of an angle in 2-space).

A scanner is definitely a better tool for the job, assuming, of course, I still had a good scanner on hand.

Originally Posted by davidfor

If the recovery partition is still intact, would it be better to use the u-boot.recovery file that is on the recovery partition? That has the advantage that it should mean it matches the rest of the files used in the recovery and means you don't need to download the firmware package before trying this.

It's also a good idea to create an image of the microSD card before attempting the recovery.

I ended up mounting the recovery file system on a Linux box then following the recovery script manually (it involves formatting the system and user partitions, then decompressing a file to each file system). That seemed to be a lot safer than messing around with the bootloader.

[davidfor]

Originally Posted by BWinmill

It's also a good idea to create an image of the microSD card before attempting the recovery.

Definitely.

I ended up mounting the recovery file system on a Linux box then following the recovery script manually (it involves formatting the system and user partitions, then decompressing a file to each file system). That seemed to be a lot safer than messing around with the bootloader.

Yes, that's a good idea and I tried it the first time I messed up my Glo. But, I messed up used an image and another card to get it working. Once I knew I had a working card, I played a bit more on the original card to see what I did wrong. I ended up using the image again, but it was a good learning experience.

[tshering]

Originally Posted by BWinmill

I ended up mounting the recovery file system on a Linux box then following the recovery script manually (it involves formatting the system and user partitions, then decompressing a file to each file system). That seemed to be a lot safer than messing around with the bootloader.

Since there is obviously a chance to mess things up, could you please share your shell command history?

[frostschutz]

If the brick is just a matter of a damaged file somewhere on the system partition, you could try to extract the entire firmware update tgz to it and see if that fixes it; if it does, no need to format after all.

Originally Posted by tshering

Since there is obviously a chance to mess things up, could you please share your shell command history?

I did this from a live USB drive so I don't have a command history available.

Writing up instructions is on my to-do list. There are simply too many requests for firmware images to ignore the recovery issue.