CEC link — cec_link

A screen's HDMI-CEC line to the television it is plugged into.

Its own contract, and its own device, because it is neither of the two things it sits between. It is not the screen — a navigator is a page somebody navigates, and turning a television off is not a thing you do to a page. And it is not the television — a tv reports which input it is on and how loud it is, and this reports nothing at all, because CEC gives a device no way to ask.

That last part is the whole shape of it. Every command here is one-way: it is sent down the wire and the wire does not answer. A television that has its own two-way driver should be driven by that driver, and a house with one takes this out of the control path — which is a decision core makes per room rather than something anybody has to switch off by hand.

Only the two operations CEC does reliably across brands: standby/one-touch-play, and Active Source. Volume is deliberately absent — it is the CEC feature sets disagree about most, and a volume key that works on one television and silently does nothing on the next is worse than one that was never offered.

Commands

tv_power

One-touch-play to wake the set, or standby to sleep it.

Parameter	Type	Notes
on	bool

tv_select

Announce this screen as the Active Source, which is how CEC switches a set to the input a device is plugged into without anybody knowing which input that is.

No parameters.