Detecting a HDMI signal

Hi all,

Arduino newbie here. I'd like to know if this project is feasible, and if so, how.

Currently, we have a HDMI cable running from a laptop to a HDMI switcher, this HDMI switchers output then runs to a few screens.

HDMI switcher info: -Installation guide -Product page

What we want to be able to happen, is someone comes along, plugs in their laptop, and the screens automatically turn on, but we don't want the screens to constantly be on waiting for a HDMI input.

We've already worked out how to turn on and control the switcher using RS232 straight from the Arduino, so controlling the switcher itself is not a problem.

My idea was to somehow hook up the Arduino to the HDMI cable which leads from the laptop to the switcher, and if a HDMI signal is detected, then turn on the switcher. Turning on the switcher itself isn't a problem from the Arduino, but we were wondering if it's possible to detect if a HDMI signal is being sent down a cable in order to perform the appropriate response on the Arduino.

If this is possible, and suggestions on parts/methods is appreciated. Thanks! :)

I think that you won't get an HDMI signal until you've connected the switcher.

Maybe you can spoof being the switcher.

Is there any way that the HDMI can go through some sort of box (such as this one, but not sure if its the right one), and then use the arduino connected to the 'middle-man' box to detect if a signal is being sent?

It seems a little weird that there's no easy way for screens to automatically turn on upon a HDMI being connected (or atleast notify the arduino somehow that the cable has been connected).

Would something like a raspberry pi be better suited for this, as in run the HDMI cable into the raspberry pi and back out again (through whatever method that would be). I'm not really sure where to start.

Thanks for the help so far!

I'm fairly sure if you look hard enough, the DVI/HDMI connection protocols are published.

see HDMI CEC protocol.

problem is the computers don't support it