K3 keyboard wave form issue....

[Tommyxx84]

Hi guys....
I'm new here....
I discovered this forum when looking for a solution for my kindle....
I gotta say that it's pretty amazing here...i didn't think there is so much that can be done with it

Anyway...

Hope that someone can point me in the right direction and help me fixing my problem....

I have a 3rd gen keyboard kindle, and i changed the display and ta daaaa....
Looks like i have bad waveform....

No gray scale at all so, it looks pretty bad at the moment.

I've already tried to do the hot swap with the old display trying to get it read from the old eeprom without luck.
I've also got another display from the seller, but same thing....

I then ended up here and found this thread that i'd like to follow, but honestly, being a newbie about kindle's sw etc, i feel a bit lost.

Can anyone maybe give me a clear step by step on how to do those things? like diagnostic mode etc....

I looked around but i haven't found a clear guide on how to do that....

I've also assumed that i needed the device rooted and i was following this thread, but files that are neccasry to JB it are not available anymore....

Any help here???

Cheers in advance!!!!

[Cinisajoy]

I think you need the developer forum.
Let me report and get you moved to the right place.

[geekmaster]

Each batch of displays has its own unique waveform tables, which vary by production run and by temperature. These are programmed following a long series of calibration tests using representative samples from each batch. The waveform data in the ROM on the display cable must match the data in the display, and some replacement displays come with NO waveform data in the ROM. In addition, there should be a voltage (between -0.3v and -2.5v) written on (or near) the cable, and that the VCOM voltage must be adjusted on the kindle motherboard to match that written value (see image below), for the best, most accurate, greyscale values on the display. Some eink devices have an adjustable potentiometer that should be adjusted to match what the replacement display requires. Other (more sophisticated) devices may have a software-adjustable voltage setting.

If the waveform tables OR the voltage are "off" for that display, it will not display accurate greyscale values.

This is GENERAL information for how these eink displays and eink controllers work (based on the early eink dev kits), but specifics may vary by kindle model in our case.

There is also a thread here dedicated to hacking waveform files to work with replacement displays:
https://www.mobileread.com/forums/sho...d.php?t=259903
https://www.mobileread.com/forums/sho...98#post2952198

[knc1]

That is one of the problems of trying to use the information from 'knock off' sites - they usual are out of date.

Prefix dropdown box: set 'tools'
Click 'show threads'
Select the NiLuJe snapshot thread -
Get your required files from there.

Ah, no we don't stop supporting devices.
With the one exception of the K1 - which never had much support here.
And Geekmaster is working to change that now.

[Tommyxx84]

yes, those are the thread that i looked before starting this one because there is no STEP by STEP guide on how to do things...

That's why i was hoping that someone could maybe list how to do this step by step in a more clear way....

[geekmaster]

I am interested in figuring out how to calibrate eink devices and build waveform tables from scratch, the procedures I read required letting the kindle test unit (one or more samples from each factory batch) settle for a long time at each required temperature (in a calibration oven) before examining contrast and distribution for each grayscale at each setpoint temperature. The waveform tables contain timing patterns for controlling grey values on the display, for each eink update mode and for a range of operating temperature.

Sadly, to do it right (if you cannot find a matching waveform table) can take many hours to develop your own custom waveform table. It may be easier just to test a collection of waveform files (harvested from a bunch of devices) to see which works best. And as mentioned above, the reference VOLTAGE must be calibrated for each eink batch as well, and that complicates the calibration procedure...

The diags firmware contains grayscale images that can be used for eink calibration.

[Cinisajoy]

I do believe this is the thread you want.
https://www.mobileread.com/forums/sho...iLuJe+snapshot
Click on what matches your device.

[Tommyxx84]

Ahhhhh..,. Too many information for a newbie..

Let's try this way....

How can i access the diagnostic mode?
Do i need to root the device first to be able to put that. Txt file into the device's root?

[knc1]

Originally Posted by Tommyxx84

Ahhhhh..,. Too many information for a newbie..

Let's try this way....

How can i access the diagnostic mode?
Do i need to root the device first to be able to put that. Txt file into the device's root?

Let us back up even further - tell us what model you have.
("3rd generation" is a marketing term.)

Use the first few characters of the device's serial number and this chart:
https://wiki.mobileread.com/wiki/Kindle_Serial_Numbers

As pointed out above by GM, some models shipped with more than a single model display during their production run.

And some models shipped with a "diagnostics mode" that you can not exit except by using a serial port connection.

[Tommyxx84]

Serial Number: B008 xxxx xxxx xxxx [full serial number redacted by moderator to protect it from the bad guys]

So based on that table, B008 Kindle 3 WiFi -> K3, K3W

Version: Kindle 3.4.2 (2687240004)

[knc1]

Super!

You win big, that is the model that shipped with three different model displays during its production run.

It is also the model that you can not exit from diagnostics without a serial port connection.

Do you have a working serial port connection on that Kindle?
If not, then any 'moving to root' will have to be done by script, not by switching to diagnostics.

[Tommyxx84]

Looks like a i won a big pain in the ass... Ahahahah
When you say "working serial port connection" what do you mean?

Let me just say that everything I've done is to change the display for a friend of mine and end up with this issue... So I'd say no, i don't if that requires some "extra tools"...

[Cinisajoy]

Originally Posted by Tommyxx84

Looks like a i won a big pain in the ass... Ahahahah
When you say "working serial port connection" what do you mean?

Let me just say that everything I've done is to change the display for a friend of mine and end up with this issue... So I'd say no, i don't if that requires some "extra tools"...

Have you tried a factory reset?

Tell me in detail everything you have done.

[Tommyxx84]

I've already tried to

- Do a factory reset
- Do the hot swap with the old display trying to get it read from the old eeprom without luck.
I've also got another display from the seller, but same thing....

[knc1]

Originally Posted by Tommyxx84

Looks like a i won a big pain in the ass... Ahahahah
When you say "working serial port connection" what do you mean?

Let me just say that everything I've done is to change the display for a friend of mine and end up with this issue... So I'd say no, i don't if that requires some "extra tools"...

One that works.

On the K3 it is relatively easy - the serial port connections are on the lower cover tab connector.

Sticky: "Where do I start?" -> K3 index -> Serial port