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How can I make a TV (a Sony W755C in my case) do a "soft power off" (same as when pressing the ON/OFF on the remote) by sending HDMI signals from a connected Mac?

I think Apple TVs can turn TVs on and off, so then a Mac should theoretically be able too. Is there a command line utility that does this, eg. hdmitool --soft-power-off?

PS! This question is a spinoff from this question which has some background on the problem.

sorin
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forthrin
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    Woot! I have this question too. Looking forward to learning what HDMI protocol allows this remote TV control. Similar to this one comment says look for ARC or HDMI-CEC – bmike May 06 '18 at 15:32
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    I don't have an HDMI TV (near my Mac at least) to test, but check these out: http://formulae.brew.sh/formula/libcec and https://stackoverflow.com/questions/15315372/sending-cec-commands-via-command-line-over-hdmi. I'm not a fan of HDMI so I typically don't use those cables, but I just might go buy an adapter to see if I can make this work. – Allan May 06 '18 at 17:00
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    libcec -l says "Found devices: NONE". https://www.reddit.com/r/osx/comments/8cg86s/ claims "Macs can't do CEC over HDMI" and you need to buy hardware: https://www.pulse-eight.com/p/104/usb-hdmi-cec-adapter. Please let me know if there is any way around this. – forthrin May 06 '18 at 17:09
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    You can't without the adapter: https://support.apple.com/en-us/HT204388 – Allan May 06 '18 at 17:35
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    @Allan: Augh!! Well, then it's back to the trusty old on/off button. You may post the Apple link as an answer and I'll accept it. – forthrin May 06 '18 at 18:27

1 Answers1

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How can I make a TV (a Sony W755C in my case) do a "soft power off" (same as when pressing the ON/OFF on the remote) by sending HDMI signals from a connected Mac?

Unfortunately, you can't.

According to Apple:

Do Mac computers with HDMI support CEC (Consumer Electronics Control)?

Mac computers don't support (and can't control) other devices via CEC connections and HDMI.

Basically, the control signals are simply not there to send to your TV. To do so, you need the USB adapter.

Allan
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