Introduction to CEC
What is CEC ?
CEC stands for Consumer Electronics Control.
CEC is a set of commands that utilizes HDMI’s two-way communication to allow for single remote control of any CEC-enabled devices connected with HDMI. For example, CEC includes one-touch play, so that one touch of play on the DVD will trigger the necessary commands over HDMI for the entire system to power on and auto-configure itself to respond to the command. CEC has a variety of common commands as part of its command set, and manufacturers who implement CEC must do so in a way that ensures that these common command sets interoperate amongst all devices, regardless of manufacturer.
CEC is an optional feature within the HDMI specification, which is supported by some manufacturers under their own proprietary names for their implementation of part of the CEC command set.
CEC uses a one-wire bus running at approx. 400 Hz and is able to send around 30 bytes per second.
CEC is already available today but with a very limited multi-vendor interoperability.
|Panasonic||EZSynch / HDAVI / Viera Link|
|Sony||Bravia Theater Synch / Bravia Link|
|Toshiba||CE-Link / Regza Link|
- Request : ask another device to take an action or give information
- Informative : status messages
- Targeted : sent to a unique device
- Broadcast : sent to all the devices within the CEC networks
- One Touch Play
- The One Touch Play feature allows a device to be played and become the active source with a single button press.
- Routing Control
- This feature is used to control the routing of the HDMI network, by controlling CEC Switches.
- System Standby
- This broadcast message can be used to switch all CEC devices to standby.
- One Touch Record
- This feature allows the user to easily start a recording of the source that is being displayed on the TV, just by selecting a Recording Device and giving the record command.
- Timer programming
- This feature allows a device (e.g. the TV) to set a timer recording on a Recording Device.
- System Information
- This feature allows devices to automatically use the same OSD and Menu language settings as the TV and also for a TV to discover the current language when it is being installed.
- Deck Control
- This feature allows a Playback Device (a deck or disc player or recorder) to be controlled by another device (e.g. the TV).
- Tuner Control
- This feature allows a device (e.g. the TV) to control another CEC device’s tuner.
- OSD Display
- This feature allows a device to transfer a text string to the TV for On Screen Display.
- Device OSD Name Transfer
- This feature is used to request the preferred name of a device to be used in any on screen display (e.g. menus), which reference that device.
- Device Menu Control
- This feature allows device menus to be controlled via the TV remote control as if it was using its own remote control and allow the TV to be aware when another device has a menu on its display.
- Remote Control Pass Through
- This feature is used to pass remote control commands received by one device (typically the TV) through to another device in the network.
- Give Device Power Status
- This message is used to determine the current power status of a target device.
- System Audio Control
- This feature allows an audio amplifier to provide the audio for a source that is being displayed on a TV.
- Audio Rate Control
- This feature allows the audio playback rate of a Source Device to be controlled by another device, e.g. an Audio System.
- Vendor Specific Commands
- This feature allows a set of vendor specific commands to be used to communicate between devices.