What is CEC (Consumer Electronics Control)?
CEC is a built-in feature of the HDMI interface and is designed to allow the user to control multiple devices (up to 10) with just one remote control (such as a TV). CEC also allows some devices to configure each other without user interaction. HDMI-CEC is a single-wire, bi-directional serial bus that functions as a remote control.
You connect a game console to the TV and adjust its settings using the TV remote control. The benefit of such a technical solution is undeniable. You do not need to constantly change the remotes. Everything can be configured with the help of a single one.
Technically, this is implemented through the 13th pin in the interface. In any bundle, the monitor or TV is considered the main device, and all the rest are adjusted to it.
Technology names for different brands
Different manufacturers of household appliances and electronics have developed their own technologies based on the CEC protocol. Here are the most famous names:
|VIERA Link EZ-Sync
|NetCommand for HDMI
Technical implementation of the interface
CEC is implemented as a trunk wire in the HDMI connector. This allows devices that support this interface to interact with each other. The main idea of the “product” is to control one remote control – several devices.
To perform specific actions, operations can be exchanged between linked devices (for example, recording to STB/DVR) or receiving general information. For example information about pressing a specific key on the remote control.
In any installation with HDMI – the display is considered the default device and receives two dedicated labels, a physical address (0.0.0.0) and a logical address (0). At any point in a given system, all CEC devices have both physical and logical addresses. At the same time, devices that do not support CEC have only physical addresses. Physical addresses are processed based on location to the default device. For example:
- If the output of the A / V – the receiver is connected to the HDMI1 connector of the TV. It receives the physical address 126.96.36.199;
- When connected to the second port, you get 2.0.0.
Logical addresses are assigned to devices based on their functionality (as provided in the CEC specification document). When the menu of an HDMI device is displayed on the display. (On the Sony KDL46EX720, this is achieved by pressing the Sync button). The display sends a signal over the CEC wire to all connected devices.
After that, responses are collected and the user is provided with a list of CEC-compatible devices. Selecting one of these will ensure that future remote keystrokes on the remote control are immediately transmitted to the TV.
How to setup HDMI CEC?
In the vast majority of cases, you do not need to configure anything additionally: after pairing the two devices, they recognize each other. With the help of the TV remote control, you can now control, for example, the receiver.
However, the standard TV remote may not have some necessary commands. In this case, it is rational to use the so-called multi-controller – a universal gadget with a bunch of buttons.
How to disable this protocol?
Through the menu of the device that is paired with the TV or monitor. If the technology is supported, there will definitely be an option in the menu to deactivate it.
Using CEC, you can issue the following commands to paired devices:
|The device becomes a signal source – video and audio streams.
|The entire system goes into standby mode.
|Tuner settings are exported to another device.
|The recording starts immediately.
|One device controls the other’s timer.
|Checks all system parameters.
|Controls the tuner of another device.
|TV is used to display text
|Switching between signal sources
|Transmits the device name to the connected TV