Panasonic 11G/12G/13G black levels have seemingly doubled overnight? - Page 360

I don't know if there is still someone interested in this, but I was able to fix this issue . I don't know if my black levels are completely reset, but there is an improvement.

Here is what I did:

1. Remove the rear cover and rear terminal cover, so you can access the A-Board
2. There is a 11 pin connector for factory adjustment. connect an i2c master (I used an AVR with my own firmware) to pin 8 and 9 and pull 10 to GND, which will mute other masters on the bus.
3. The panel eeprom has the address 0xa0 but is unfortunately write protected. Remove the write protection by pulling the following VIA to GND (I used a thin wire).
   
4. Now we can write to the eeprom. the panel aging is saved from 0x0001 to 0x0006 (right at the beginning ). Just set these 6 bytes to zero and you're finished. Note that this is not the same clock as in the PEAKS EEPROM, which was already reset by other users with no effect.

I don't have much time now, but if there is interest in this i can write a more detailed HOW-TO. Perhaps we can find even more settings in this EEPROM.

Here is the result:




Thanks to everyone in this thread for valuable information!!

What an incredible 1st post!

Agreed! This could be the post of the year

Please PLEASE PLEASE give us a more detailed how-to. Also, if you could mention what model you did your modification on, and whether it would be applicable to other Panasonic models.

Thanks for a great post!

I keep checking the calendar to make sure it's not April 1st! This is amazing and unexpected news -- if you post a detailed How-To guide, you will surely go down in AVS history! THANK YOU!

You could start your own business resetting black levels, $100 a pop and I'll be your first customer!

Best post, ever. Made quite a difference. Mucho kudos.

A couple of questions:
1. How long can we expect this fix to last?
2. Will performing the fix mean that all other settings will have to be changed? Or, if not which ones?
3. And just out of pure curiosity, how did you figure this one out? What is your field of expertise?

Wow, nice that you were able to get this to work on your TC-P50V10.

IC9003 pin 10 is marked "P20" in the service manual, and this chip appears to be used on Panasonic 2008 plasmas and newer.

This was done on a TX-P42S10 from germany, I don't know the model number in other countries. I'm pretty sure that this will work on all the models of that generation. I also guess that current generations use i2c bus too, but perhaps there are differences in EEPROM addresses and layout/design.

The clock will start from zero, so you need to do this again after your blacks rise again. But I am thinking about an ATtiny which I would program to reset the value periodically, eg. once an hour. The only Problem is the write protection of the EEPROM. Without the write protection there wouldn't be a reason to open the case, everything could be done from the adjusment connector. Im sure there is a way to disable the write protection over the service connector, but i couldn't figure out how.
No other settings are affected by this, you just set the age of your panel. But it is possible that setting the panels age has influence on other voltages too, because this value is used to configure the panels processor each time you switch your tv on.
I am studying electronic and information technologies with focus on telecommunications. With the service manual and schematics it was really straight forward to hook into the i2c bus. At first I used an AVR to monitor the bus. I was able to see when which part of the EEPROM was written or read. Then I dumped the hole EEPROM, waited a few minutes, switched TV on/off and dumped it again. I compared the different dumps with a diff viewer and found the clock quickly.

I really hope that some of you dump their EEPROMS too. By comparing them we could find more values for tweaking. And we could test alot, because I don't think we need to be afraid of bricking our TVs, since we can flash the original hexfile into the EEPROM whenever we want. By the way, the PEAKS EEPROM (digital video processing) and the STANDBY EEPROM are also accessible over the i2c bus, but I just dumped them, didn't try to tweak anything yet...

I will write a HOW-TO this weekend, but be aware that you will need an i2c master for this. I am glad to see you still interested in this!

[HOW-TO] Resetting the panels age

This How-To applies to the TX-P42S10 model, in the hope it applies to other models too.

1. Disassembly: Remove the screws you can see in the picture and remove the rear cover.
   
   Remove the claw on the top of the side terminal, then remove the side terminal.
   
   Remove the screws you can see in the picture and remove the rear terminal cover. The location of the adjustment connector is marked red.
   
2. You should now see the following adjustment connector:
   
   I found a matching counterpiece in an old DVD-player, but it's up to you how you connect to it. The pin assignment is (from the top):
   
   Code:

   1 +5V
   2 SRQ (probably Service Request)
   3 GND
   4 GENX8_SCL (STBY EEPROM)
   5 GENX8_SDA (STBY EEPROM)
   6 PEAKS_SCL (PEAKS EEPROM)
   7 PEAKS_SDA (PEAKS EEPROM)
   8 PANEL_SCL (PANEL EEPROM)
   9 PANEL_SDA (PANEL EEPROM)
   10 I2C_CONT
   11 D_PCB_MODE (Process Control Block or Printed Circuit Board?)
   

   
   You now need an i2c master, a device which can read and write on an i2c bus. I used an ATmega which I programmed by myself, I will release the source code on request. But perhaps you can find something on google. Try searching for "USB i2c interface". This is german, but as an example:
   http://www.elv.de/usb-i2c-interface-komplettbausatz-inkl-gehaeuse-bearbeitet-und-bedruckt-usb-kabel-3-anschlusskabel.html/refid/googlebase
   The i2c bus (aka two wire interface) consists of the SCL and SDA lines. As you can see, there are three different busses. On each bus are multiple devices, each with it's own address. But on each of the three there is an EEPROM with the address 0xa0. Reading from an EEPROM is done by addressing it and then writing two bytes which contain the position you want to read. Next, address the EEPROM in read mode and read as much bytes as you want. You can now verify if your i2c master works by connecting it to the PEAKS or STBY EEPROM and read something. As you can see these EEPROMS also in the Service Menu, you can check if you're doing it right. For reading from position 1, write 0x00 0x01 to the EEPROM, then start reading.
   
3. Now, connect your i2c master to the PANELS EEPROM. Then connect I2C_CONT to GND, so no other masters will talk on the bus. Since the EEPROM is write protected, you need to connect the following VIA to GND. You can find it on the top-left of your A-Board.
   
   But be careful, connecting something else to GND can damage your hardware. So I suggest attaching a thin wire to the VIA while the TV is switched off and connecting it to GND while writing to the EEPROM. You should also recheck if this VIA is attached to the EEPROM if you are using another TV model.
   If the write protection VIA and I2C_CONT are grounded, you can start writing to the EEPROM. Writing is similar to reading, first start an i2c transfer by addressing the EEPROM (0xa0), then write the position where you want to write (0x00 0x01), then write the new bytes (0x00 0x00 0x00 0x00 0x00 0x00). This will set the bytes one to six to zero. These bytes contain your Panels age. To check if you were successful, read the bytes out again. You should see an improvement on your black level after switching the TV off and on again.

I hope this will help anyone.

I dumped two EEPROMs of two different TX-P42S10. Perhaps someone is interested in this. One of them is version 33.01, the other is 33.00. In the 33.01 the clock was reset by me. The 33.00 version is not modified.

panel_e2p-33.00.txt 25k .txt file
panel_e2p-33.01.txt 25k .txt file

Thank you so much, clktmr, for posting this how-to, and differentiating the pins on that 11-pin connector.

I haven't fully explored everything yet, but Panasonic does allow data setting transfers between A-boards, when an A-board is replaced during servicing. Probably so settings can remain the same and transparent to the owner.

This document explains the procedure using a SD card, starting at page 85. It says that it copies customer setting data, channel scanned data, adjustment data, and shipping data. I'm not sure what all that means, but if an A-board is replaced, I would think the panel usage hours would be important to transfer also.

I haven't had the chance yet to copy my data onto a SD card and examine the contents, to see if the hours are indeed copied. But if the hours are copied, it may be simple to change those hours before copying that data back onto the A-board.

Also, that pin 10 on IC9003 is underneath the chip on my set, and inaccessible without removing the board. However, according to the service manual, it ties into pin 7 of EEPROM IC9001, and called EEP_WR_CTL.

Agreed. I just tried this, but I couldn't find the clock in the data on the SD-Card. Also, I don't know what the svl_file contains. Perhaps it is encrypted or saved in another format.

Have you tried to save that file twice, with a few hours in between with the TV on, and compare the two files?

VMat

This is some awesome info...has anyone made any progress with the SD method? Much appreciated your efforts CLK!

wow I can't believe someone actually figured out how to fix this after all this time-- amazing work! I too would be super interested in the SD method-- the TV I wish to fix isn't mine, so I don't PARTICULARLY want to go messing around on the inside... but just letting you know theres more interest--- it wasn't super easy to find this on google! hopefully bumping this thread will keep some interest going...

I am interested as well.....I would like to hear more on this.

I would be very interested in this as well, if it is possible via the SD card. Thank you for looking into this.

Yes I would be interested as well. Im not comfortable with tinkering in the back just yet.
58V10 still looks great, but woudl love for it to look better....

I would be interested as well , but we do not know for sure if the hours are copied with all of the other A-board settings.
Edited by rczarne - 10/25/12 at 3:11pm

Dammit. Just when I got rid of my GT20 here comes the solution. I'm happy for everyone out there who can prolong their TVs performances.

I'd be interested in trying a simple SD Card type fix, just as long as it doesn't degrade the life span of the TV.

I thought it was the general consensus that the rising black levels issue was detrimental to the increased rated life span. Of course I understand few of us here would be keeping the same TV for upwards of 10+ years anyways.

I, too, would be interested. I am curious however if it is absolutely REQUIRED that you solder-mod the board, or if the EEPROM signal can be grounded through some other connection mechanism. Do you have a copy of the schematic? I'm surprised that the EEPROM isn't software upgradable. I actually have a 50G10, but no schematic for it. I think someone gave me a schematic a while back for an S10, which I'm sure has very common circuitry. I also already went to the hassle a few years back of getting several connector samples, I think for the very one you mention, when there was active work being done on the I2C bus to try and solve the problem. I myself ran out of time to work on it any further, though I still have the connectors and S10 schematic.

keep us posted..

..dane

If you are interested in a manual for your G10, try here: http://elektrotanya.com/?q=keres

I'm still interested in this as well.

Sweeeeeet! Thanks so much!

..dane

Nice work!
But do you know what could be even better...? -> Finding a way to tweak the black levels (manipulate the pre-discharge control parameters in the EEPROM until you find the sweet spot of your own panel)!

Still no solution using SD card?

+1

Fixing this problem by manually programming the EPROM is a fantastic achievement. But few end users would be capable of fixing their black levels this way.

An SD card solution would reach SO many more people. But to me that seems like it would add an entire additional level of complexity.

Updating via SD card is fantasy.

It's going to be an expert level task. That's why Panasonic never admitted to this to begin with.

I'm kinda glad Panasonic has this "prices cant drop x% policy". I'm contemplating upgrading the 50V10 to a 60 incher & relagating the rising black tv to the basement. But I cant justify $1900 for a 60G50 when there are 60 inch models for $699-$999 this black friday.