Audio Return Channel in HDMI 1.4 - AVS Forum
Forum Jump: 
 
Thread Tools
post #1 of 7 Old 05-18-2011, 04:47 AM - Thread Starter
Newbie
 
fima.koreban's Avatar
 
Join Date: May 2011
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Hi.
I have a technical questions regarding the audio return channel, a new feature that is supported in HDMI 1.4.
I have read about this feature, but i have some technical questions.
How the TV switches to ARC mode? i have read about the CEC commands that trigger this mode, but what triggers the TV to send them?

Thanks a lot
fima.koreban is offline  
Sponsored Links
Advertisement
 
post #2 of 7 Old 05-18-2011, 08:50 AM
 
alk3997's Avatar
 
Join Date: Jan 2004
Posts: 3,722
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 88
Quote:
Originally Posted by fima.koreban View Post

Hi.
I have a technical questions regarding the audio return channel, a new feature that is supported in HDMI 1.4.
I have read about this feature, but i have some technical questions.
How the TV switches to ARC mode? i have read about the CEC commands that trigger this mode, but what triggers the TV to send them?

Thanks a lot

The TV has to have the feature built-into it, as well as the receiver. If the TV supports the audio return channel, then I suspect the EDID would take care of switching it on/off - in other words the user would not need to do anything. The components would handshake and if both of them supported the audio return channel, the feature would be enabled - much like how resolutions are chosen.

Maybe someone with an ARC TV can confirm?
alk3997 is offline  
post #3 of 7 Old 05-18-2011, 05:08 PM
AVS Special Member
 
Colm's Avatar
 
Join Date: Aug 2002
Posts: 4,652
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 89
The AVRs I haved seen that support ARC require you to select it in the TV audio section of the menu. But apparently some will switch on receipt of an appropriate CEC command. Of course, this requires a TV and AVR that support the appropriate commands. CEC commands from a TV are typically triggered by some user action, such as hitting a key on a remote, or making a selection in a menu.
Colm is offline  
post #4 of 7 Old 05-19-2011, 01:26 AM - Thread Starter
Newbie
 
fima.koreban's Avatar
 
Join Date: May 2011
Posts: 2
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 10
Any one can recommend TV/AVR with this feature?
Anyone who used it, can you confirm that TV toggles ARC mode once you switch to TV tuner input? Does it also mean that TV holds HPD active on the HDMI even when it is not the active source?

Thanks
fima.koreban is offline  
post #5 of 7 Old 05-19-2011, 01:36 PM
AVS Special Member
 
Colm's Avatar
 
Join Date: Aug 2002
Posts: 4,652
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 89
I think by now most major manufacturers are offering some models of TVs and AVRs with ARC.

I suspect that ARC works just like any other digital audio output on the TV. It just eliminates one cable.

To find out how HDP functions with ARC, you will have to check the the HDMI 1.4 specification, which will be difficult considering you are not an adopter. It might be easier to find the information in documentation from one of the HDMI chip makers. I think it is irrelevant, though. The AVR will likely play whatever comes over the ARC when the TV is selected as the input, just like it will play whatever comes over the Toslink or coax cable when that is the connection and it is appropriately selected.
Colm is offline  
post #6 of 7 Old 05-19-2011, 01:55 PM
 
alk3997's Avatar
 
Join Date: Jan 2004
Posts: 3,722
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 88
Some discussion about this here:
http://ez.analog.com/thread/5843

I also think I understand why an AVR would need a menu item. The audio input would normally be through the HDMI/toslink/analog inputs. If ARC is selected then the only way the ARC input would be selected is if there was a menu override.
alk3997 is offline  
post #7 of 7 Old 05-19-2011, 02:05 PM
AVS Special Member
 
Colm's Avatar
 
Join Date: Aug 2002
Posts: 4,652
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Liked: 89
Likewise, on a TV, you typically have to select whether to output audio to the TV's speakers or ARC or other digital audio output.
Colm is offline  
Reply HDMI Q&A - The One Connector World

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page


Forum Jump: 

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off