HDMI Ethernet Channel - Would it work?


11 posts
by Spider.007 » Wed May 23, 2012 8:17 am
I am not too familiar with Ethernet over HDMI, since I don't own any devices that support it, but I was wondering; would it be possible (in the future) to use this feature on the RPi? Is there anything physically allowing or preventing usage of this?

More information on HDMI Ethernet Channel
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by mahjongg » Wed May 23, 2012 9:40 am
The SoC doesn't support the ethernet channel, (I have heard) so no it won't ever be supported.
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by JeremyF » Thu May 24, 2012 1:38 am
The HDMI port can not receive Ethernet signals. Since it is related topic, the Ethernet cannot receive power. (PoE)
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by ds18s20 » Tue Jul 17, 2012 8:01 pm
I can confirm: NO Ethernet via HDMI. I plugged my Raspi into my Bravia TV and the TV does not report the Ethernet HDMI interface as active.

When I plug my Blu-ray player (which supports Ethernet over HDMI) into the same HDMI port on the TV then the HDMI Ethernet interface shows up as active using the Bravia diagnostics screen under system menu.

Oh well...
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by tediffer3rd » Thu Dec 27, 2012 10:55 pm
Then how can I control my 512 meg RasPi with my TV remote?
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by toxibunny » Fri Dec 28, 2012 12:01 am
note: I may or may not know what I'm talking about...
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by adammw » Tue Jun 11, 2013 11:26 am
Do you know if the SoC also does not support HDMI ARC? Both are part of the HDMI 1.4 spec. What exactly in the SoC is preventing this sort of data from being accessible to the cpu, why does it allow CEC access but not the other channels? Or is it related to the closed source parts of the firmware?
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by drgeoff » Tue Jun 11, 2013 5:58 pm
adammw wrote:Do you know if the SoC also does not support HDMI ARC? Both are part of the HDMI 1.4 spec. What exactly in the SoC is preventing this sort of data from being accessible to the cpu, why does it allow CEC access but not the other channels? Or is it related to the closed source parts of the firmware?

From Wikipedia's page about HDMI:

"HDMI 1.4 introduces two features called ARC (Audio Return Channel) and HEC (HDMI Ethernet Channel).[58][59][93] These features use two pins from the connector: a previously unused pin and the hot plug detect pin."

If the previously unused pin does not go anywhere in the Broadcom SoC (I don't know) then whatever feature needs it now will never work. Similarly there may be an internal hardware limitation which prevents use of the hot plug detect pin for other than what was in the SoC's original requirements specification.
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by rpdom » Tue Jun 11, 2013 6:07 pm
It would help if that article said which pin was "previously unused", as the Pi schematics are freely available to check.
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by drgeoff » Tue Jun 11, 2013 7:34 pm
rpdom wrote:It would help if that article said which pin was "previously unused", as the Pi schematics are freely available to check.

It does say. Look underneath the first picture on the right hand side. There is a list of the pins and it specifically mentions Reserved/HEC for pin 14.

Even if the HDMI socket's pin is connected to the SoC, that doesn't mean it goes anywhere useful inside the SoC!
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by jamesh » Tue Jun 11, 2013 9:18 pm
No, the SoC does not support ethernet over HDMI.
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