This is a simple connector to expose an HDMI-CEC adapter (e.g. PulseEight, possibly Raspberry PI) via MQTT.
This tool is primarily meant to be run from a docker container.
docker run --privileged -e MQTT_URL=tcp://localhost:1883 -v /dev/ttyACM0:/dev/ttyACM0 tobiasha/hdmi-cec:latest
Note that privileged mode is required to be able to use the HDMI CEC device and the device needs to be mounted into the container. Depending on the type of CEC adapter you might need to change the device name.
A sample Kubernetes deployment file is provided in the deploy subdirectory, it
can also be used as a kustomize base.
If you want to build the tool yourself or use it without docker, check the
Dockerfile for build details. CGO is required!
Compile dependencies:
libcec-devudev-devp8-platform-dev
It should be possible to build and use this for a Raspberry PI, but I haven't tested that yet and do not have a pre-made Docker image for it at this time. PRs welcome!
Configuration is exclusively done via environment variables:
| Name | Default | Description |
|---|---|---|
| MQTT_URL | MQTT Endpoint URL | |
| MQTT_USERNAME | MQTT Username | |
| MQTT_PASSWORD | MQTT Password | |
| MQTT_TOPIC | cec | MQTT Topic prefix |
| CEC_DEVICE | /dev/ttyACM0 | CEC device file |
The prefix /cec is the default and can be switched by specifying the
CEC_DEVICE environment variable. Some operations require you to specify a
device logical address, it can be determined by reading from the /cec/list
topic. Usually the TV seems to have logical address 0.
The tool will continuously poll the list of HDMI devices and push it to this topic. It should be treated as read-only for users. The list will also contain the logical address of the connected devices that is required for some operations.
Publishing to this topic will transmit the given payload as arbitrary HDMI-CEC command. See for example cec-o-matic for details.
Publishing to this topic (payload is irrelevant) will toggle the mute status.
Publishing to this topic sends the key specified in the payload to the HDMI
device with the logical address. See the cec
library for valid key
names.
Publishing the payload on to this topic will turn the device with the given
logical address on, publishing any other value will turn it off.
Publishing the payload up will turn the volume up, publishing any other
value will turn it down.