Consumer Electronics Control

Consumer Electronics Control (CEC) is a feature of HDMI designed to allow users to command and control devices connected through HDMI by using only one remote control. For example by using the remote control of a television set to control a set-top box and or DVD player. Up to 15 devices can be controlled. CEC also allows for individual CEC-enabled devices to command and control each other without user intervention.

It is a one-wire bidirectional serial bus that is based on the CENELEC standard AV.link protocol to perform remote control functions. CEC wiring is mandatory, although implementation of CEC in a product is optional. It was defined in HDMI Specification 1.0 and updated in HDMI 1.2, HDMI 1.2a and HDMI 1.3a (which added timer and audio commands to the bus). USB to CEC adapters exist that allow a computer to control CEC-enabled devices.

Trade names for CEC are:

The following is a list of the most commonly used HDMI-CEC commands:

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