How does a HDMI handshake work?

Trevor

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I have a question about HDMI that I can’t post in the Tech Talk forum as I don’t have the privileges.

I am trying to resolve an HDMI issue between my Mac Mini and my LG TV, which I use as a second display. The interface between the two works fine if I use a USB-C port and an HDMI adapter.

However, when I use the HDMI port on the computer it does not recognize the TV consistently. I have tried talking to Apple support, but they blame the TV. There are many others out there with the same issue on many other different TVs.

Before I get into any specifics, could someone direct me to somewhere that I could learn how the HDMI handshake works? I would like to understand more before I start asking detailed questions.
 

tripplej

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Trevor

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Hi trippleJ,

Thank you for your reply, I have read the links you listed. That one particular TV setting did not resolve it for me.

I do not have a consistent set of symptoms to give you, but the TV is intermittently recognized through the HDMI port whereas the TV is always recognized through the USB-C port (with HDMI adapter).

My gut feeling is that the HDMI handshake between the two fails, and is not reattempted. I believe it is supposed to keep trying, and maybe it is but I don't know how to tell. How often should the handshake be occuring, and which unit sends the invitation to communicate; the computer or the TV?
 
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