Is HDMI bi-directional?

[Sauron]

So I have a question.

Does HDMI carry data streams in a bi-directional manner?

I have a TV that is connected via HDMI to a Yamaha receiver + speakers. If it's bidirectional, then sound from the TV should go to the receiver, and out the speakers.

Likewise, the UI interface for the Yamaha receiver (menu, options, etc.) should be viewable and editable on the TV.

But it doesn't seem to work that way.

I can't get any audio from the TV unless I also plug in the digital audio out cable (very thin cable that plugs into with red laser connection ports on both ends).

Am I doing something wrong?

Thanks.

[ChuckF]

Some HDMI cables are directional, especially if they are long. I ran like 50' of it through the ceiling and down the wall and up through a table at work for the projector before I found this out.

[lisarea]

This is weird, because I have been trying to figure out this near identical thing. I have a newfangled TV (optical and 3.5 headphone output, plus HDMI and other inputs) and an oldfangled receiver (RCA inputs only) that I want to sent audio to.

As I understand it so far, yeah, it should work both ways according to HDMI specs, but the chip in your TV is limiting the functionality, and that's not something that you can modify. It's one of those anti-features.

If a smarter person comes to answer, though, I would love to find out I'm wrong. (And also what my options are. I'm considering just sending the audio to the receiver through the headphone output to see how that sounds.)

[ceptimus]

HDMI ports on TVs that support both receiving and transmitting sound are sometimes marked 'ARC' (stands for 'Audio Return Channel'). Often a TV will have several HDMI ports but only one of them will usually be ARC-capable; this is also true for other devices like laptops - you need to connect two ARC-capable ports to each other to get it working.

ARC was only introduced in the 1.4 HDMI specification, so really old devices with HDMI won't support it. The ports aren't always marked 'ARC', but if you have a manual it might tell you which port(s), if any, is/are the ARC one(s).

The HDMI cable has to be rated 'high speed' - this doesn't mean it has to be expensive, it's just a different cable specification.

In theory you can send all sorts of other info via the HDMI - which might allow you to, for example, use the TV remote to control your BluRay player or whatever. The trouble is that different manufacturers have different ways of implementing it, so it's tricky to get stuff working unless it's all the same brand.

[JoeP]

The joy of standards.

[Dingfod]

My 42" LED flat-panel TV doesn't have ARC HDMI.

#FirstWorldProblem