Page 1 of 1

OT- HDMI CEC

Posted: Thu Feb 25, 2016 7:36 pm
by vickyg2003
Hi guys, somewhat off topic. I've seen CEC mentioned several times in this forum.

Our condo association has a clubhouse with two large TV's connected via a 5x2 iogear matrix. The xfinity HD cablebox, and DVD player and other equipment is set up in a locked room, but there is some sort of ir dongle on the wall by the main TV. I was only allowed access to the Sony Bravia Remote control, not the comcast remote. I was told that the sony remote should take care of the channel changing on the xfinity box. Which it didn't. I had to go get the staff to get a key and enter the out of bounds AV room, to change the channel with the comcast remote.

The CEC to turn on the xfinity box is definately working. Should a Sony TV remote be able to somehow force the comcast box to change channels? Or did the keeper of the keys totally misunderstand what her professional installer told her?

If the TV really is supposed to control changing the channel, what needs to be done at the TV level, and would I need access to the xfinity box?

And BTW which comcast codes tend to be for the HD xfinity boxes?

Posted: Thu Feb 25, 2016 8:06 pm
by The Robman
I don't know anything about CEC, so I Googled it and found this quote from graham...

re: https://www.hifi-remote.com/forums/viewtopic.php?p=96450
mathdon wrote:I understand that Sony equipment, however, is deliberately crippled so that HDMI-CEC only works with other Sony equipment. Hence no Sony in my setup.

Posted: Thu Feb 25, 2016 8:32 pm
by mdavej
On most devices, CEC is limited to power and input commands. For example, turning on a CEC enabled cable box or disc player would send power and input commands to other devices in the chain, so all end up powered on and on the correct input to see that device. I've never heard of any cable boxes with any more than this, no channels, no transport controls. So Vicky, there is no possibility channel commands would be relayed to your cable boxes.

If you look at a fairly complete sony TV upgrade, you'll see a set of BS (Bravia Sync) commands. These are all CEC. So if you send a BS-Play command to the TV, it gets relayed over HDMI to a connected disc player. I've used these extensively with disc players and game consoles. Those kinds of devices typically implement many more CEC commands.

Posted: Thu Feb 25, 2016 9:03 pm
by vickyg2003
mdavej wrote:So Vicky, there is no possibility channel commands would be relayed to your cable boxes.

Thank you so much. I was under the impression that the keeper of the keys was wrong. She was told we'd only need the one remote, which I'll dare bet was the Comcast remote! But when you are an "inmate" at a condo association, you are not supposed to know anything!, lol.