Consumer Electronics Control

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Consumer Electronics Control ( CEC ) provides cross-component control functions such as “One Touch Play / Record”, “System Standby”, “Preset Transfer” etc. for electronic consumer devices. The CEC interface has been derived from AV-Link as the control standard that has prevailed in Europe up to now .

Ideally, a maximum of 15 devices (e.g. television, radio, CD player, amplifier, etc.) can be controlled jointly from all manufacturers, provided all networked devices support CEC. An essential design basis is the television set as the target of all signals and the remote control of the television set as the operation of the overall system. Because of this "one-screen" approach, problems inevitably arise with HDMI distributors and in multiroom systems, because there are naturally several destinations, which CEC does not provide for addressing. Apart from the general waiver of CEC, this problem can only be solved by systems that allow the isolation or routing of the CEC traffic independently of audio and video signals.

CEC uses a simple serial, single-wire data bus , such as B. for HDMI connections (on pin 13) is optionally available. The nominal data bit duration is approx. 2.4 ms, which corresponds to a data rate of approx. 417 bit / s. The connection is established and the check for CEC capability takes place in the course of the EDID handshake at the hot-plug event. This occurs when the devices are switched on or when an HDMI connector is inserted into an HDMI socket.

CEC function list

Many of the following functions were initially not mandatory in the HDMI specification, so that different devices have completely different CEC implementations. It was not until HDMI 1.3 that many functions were specified and many of the initial difficulties of CEC were resolved.

Deck control
allows a device (e.g. television) to control playback via a playback device
Device Menu Control
enables one device to use the menu of another device
Device OSD name transfer
forwards the preferred device names to the TV
One touch play
allows a device to play instantly and become the active source
One touch record
starts the immediate recording of the program currently shown on the TV
OSD
allows a device to use the TV's OSD ( On Screen Display ) to display text
Preset transfer
allows a tuner to take over all station settings of a connected TV set
Remote control pass through
allows remote control commands to be passed on in the system
Routing Control
controls the switching of signal sources
System information
examines all connected system components for their bus addresses and configurations
System standby
switches all connected devices to standby
Timer programming
allows a device (e.g. television) to timer- program a recording device (e.g. DVD recorder )
Tuner Control
provides a device with the tuner control of another device
Vendor Specific Commands
are manufacturer-dependent, device-specific control functions

Manufacturer designations

Many manufacturers use their own brand name for HDMI-CEC:

Web links