CEC (Consumer Electronics
Control) is a feature of HDMI designed to control multiple devices connected
over HDMI by using a single remote controller. A common application of this is
having a source, such as a Roku, connected to an AVR, then going out to a display.
Turning on the Roku will also turn on the AVR and the display.
CEC is a single wire bus in the HDMI connector (pin 13) and allows for different
devices to discover and communicate with each other. Since this is a
bidirectional serial bus that is directly connected between the devices, it
also allows control for a function named “One Touch Play”. One Touch Play sends
a series of commands to multiple devices in the system (the CEC Network), allowing
a device to be played and become the active source with a single button press.
Other common CEC commands are System Standby, Audio System Volume Control, and
Source Menu Control.
AVPro offers drivers for third-party control systems, allowing for further
customizable programming and commands to integrate our matrixes into any
installation. These drivers are developed with many customers’ feature requests
in mind. Examples include CEC control encapsulation and the ability to disable output
streams to a particular zone, such as an HDMI display that may power off when
an HDMI source isn’t present.
Sources
may need to send an active 5-volt (minimum 55mA) current to power a device’s HDMI
input bus for CEC. When using AVPro Edge
devices, sending a Stream Off command will disable the 5V Output; causing CEC, hot
plug detect, and EDID information (DDC) to not be seen.
Managing CEC and other HDMI signals can be challenging.
Interoperability between sources and displays, content changes that alter
signal type, and HDCP constraints can cause havoc on the installation. Diagnostic
and troubleshooting tools located directly within AVPro Edge’s AVPro Edge User
Interface (AEUI) and the MXNet Mentor HTTP Interfaces can help ensure
compatibility and stability between all the devices in your HDMI system.