HDMI CEC

[cleemansen]

https://en.m.wikipedia.org/wiki/Consumer_Electronics_Control

[cleemansen]

Debug session:

echo "scan" | cec-client RPI -s -d 1
# raspi is the `CECTester`

• https://www.cec-o-matic.com/ Most interessting commands are in section End-user features > System Audio Control > User Control Pressed

# volume up
# source: Recording 1
# destination: Audio system
echo 'tx 15:44:41' | cec-client RPI -s -d 1