Fix for CEC Communications Bravia Sync / Samsung anynet+ etc

[Mede8er1]

We have identified that the MED400X & MED500X is adding to much capacitance on the HDMI CEC line ie PIN13. Max allowable is 100pF and the MED hardware has a 100nF bypass cap. We have had a positive response from a Mede8er owner who removed the Capacitor as indicated in these images and this solved his CEC problems with Sony Bravia equipment.

Pls feel free to try this but we suggest if you are not experienced at PCB work to let a local techincian do the removal for you. lt should not take longer than 5 min for the whole procedure.

MED500X
http://www.mede8er.org/artwork/temp/pin13_cap_MED500x.jpg

MED400X
http://www.mede8er.org/artwork/temp/pin13_cap_MED400x.jpg

IMPORTANT  XXXX   This modification should only be carried out if you are experiencing CEC problems on the HDMI line

This modification will not affect the Mede8er warranty as long as it is carried out correctly and no surrounding components are damaged during the process.  If you are in doubt then we suggest you contact your local distributor.

Mede8er1
  




    

[JPF]

Any reply from Panasonic users with Viera link problems?

And why remove this one from pin 15 (Display Data Channel) while pin 13 gives the problem?
Or is this just my optical mistake when I look at the picture:
http://www.mede8er.org/artwork/temp/pin13_cap_MED500x.jpg

What other restriction will give this modification to the display adjusting parameters?

The Display Data Channel or DDC is a collection of digital communication protocols between a computer display and a graphics adapter that enables the display to communicate its supported display modes to the adapter and to enable the computer host to adjust monitor parameters, such as brightness and contrast.

[jer1956]

You are right. It does look like the capacitor circled connects to Pin 15, not Pin 13.

[Maasbommel]

Difficult to see if you don't have a drawing of the circuit.

[tachita_]

It is about capacity load in entire circuit.
Maasbommel is right about this , but a circuit drawing will not help for unadvised eyes. A circuit layer picture can be very tricky and for that cap there is no need to be connected to pin 13

[Maasbommel]

As far as I know several people have implemented this fix with success.
Only way to be sure if it is working in you situation is to remove the cap.

When done as advised, it can be placed back when it does not give a solution with the same method.

[tachita_]

i didn't test this because it was no need for me , but insteed of removing completely i will replace that CAP with lower value : 50pF or 30pF (i cant tell the right CAP value, becuase i didn't measure the equivalent capacitance of m8r circuit withoud that cap ).
this will avoid unwanted side effects.

[jer1956]

It seems this "fix" must turn the Med into a HDMI 1.3a CEC device:-

 http://www.audioholics.com/education/display-formats-technology/understanding-difference-hdmi-versions

[Gruff]

Hi, what would the benefit be to get CEC functionality on the Mede8er? I can understand the benefits of using CEC for an AMP, TV, DVD combination, to be able to turn on and off all the devices and adjust volume and so on.

Would CEC also allow the Mede8er on/off and volume to be controlled from the TV remote as well?
My knowledge of CEC is fairly limited.

Cheers
G

[jer1956]

Hi, what would the benefit be to get CEC functionality on the Mede8er? I can understand the benefits of using CEC for an AMP, TV, DVD combination, to be able to turn on and off all the devices and adjust volume and so on.

Would CEC also allow the Mede8er on/off and volume to be controlled from the TV remote as well?
My knowledge of CEC is fairly limited.

Cheers
G

The problem is the Med's sec line is not properly identifying it as "unused" and cuases CEC to fail in other devices. The "fix" dosn't enable CEC in the Med, it just gets the Med's CEC line to properly appear as "unused".

[tsgold]

Hi,

i've notice that there is a new firmware update for MED500X (below)

http://www.mede8erforum.com/index.php/topic,4793.msg32427.html

Can I check if this Firmaware would solve CEC comunication issues? I just purchase new Panasonic TV with HT System and it's a waste if I cannot use HDMI port as it messes with Viera Link.

[jer1956]

Firmware cannot fix the different capacitence levels used between HDMI 1.3 and HDMI 1.3a. Only the Mod described at the start of this thread can do  that.

[tsgold]

Firmware cannot fix the different capacitence levels used between HDMI 1.3 and HDMI 1.3a. Only the Mod described at the start of this thread can do  that.

jer1956 ,
thansk for the response. Just to set the right expectation, all I need to do is remove C110 indicated on the below snapshot.

http://www.mede8er.org/artwork/temp/pin13_cap_MED500x.jpg

I do not need to cut Pin 13 from the Mede8er board right?
another question, if i were to use HDMI 1.4 cable, would it help?

[Maasbommel]

Only remove the cap as posted by mede8er1, don't cut the pin 13.

Using another cable will not help.

[JPF]

I do own a "new" model 500 too now.
The one without the 3A power supply, but with the 2A.
And not a blue dot sticker on the back, but orange.

This "new" motherboard layout is slightly different.
What strikes me, is that the pin 13 in this layout is totally different.
And, as I did note before, the work around to disassemble the cap in this topic, is still possible for this motherboard.

But I do still have a lot of doubts.
Why? Because the new 500 works with CEC.
Why? Well, maybe because they changed the pin 13 resistor.
BUT, as allready told before, the cap is still there, and it is still not attached to pin 13 but pin 15.

Anybody likes to shoot?