CEC control - Pi turns TV on when booted

sleve_mcdichael

Any time I boot or reboot my RPi4, my TV will turn itself on if it wasn't already, and switch to the HDMI2 input. Can I have more control over this from the OS angle? Can I either, disable it so the TV doesn't do anything when the RPi boots, and/or is there a command I can send (over SSH, for example, or even just "blind" on an attached keyboard) that'll send the CEC signal which wakes up the TV, on-demand without doing a full reboot?

mitu

Try adding hdmi_ignore_cec_init = 1 to your config.txt.

See more details at https://www.raspberrypi.com/documentation/computers/config_txt.html#hdmi_ignore_cec_init

sleve_mcdichael

And it looks like the other side (manual control) of this is handled with cec-utils:

sudo apt -y install cec-utils

Then you can use cec-client to send commands like on, standby, or as (active source):

# turns on display 0 if it's off:
echo 'on 0' | cec-client -s -d 1

# turns off display 0 if it's on:
echo 'standby 0' | cec-client -s -d 1

# active source: powers on the display if it's not (all of them? I only have the one but this command doesn't specify which, unlike the other examples) , and channel-switches to HDMI source:
echo 'as' | cec-client -s -d 1

https://www.linuxuprising.com/2019/07/raspberry-pi-power-on-off-tv-connected.html?m=1

Retro Arcade Fan

@sleve_mcdichael said in CEC control - Pi turns TV on when booted:

echo 'on 0' | cec-client -s -d 1

I'm very intrigued by this! I never knew there would be a way for the pi to turn off the tv when it's shut down. I'd be glad to get rid of the remote.

Upon my testing, was able to turn the tv on, but not off. I installed the utils. echo 'on 0' | cec-client -s -d 1 would turn it on. But echo 'standby 0' | cec-client -s -d 1 had no effect.

Any insight? Thanks.

sleve_mcdichael

@Retro-Arcade-Fan sorry I can't be more help, I don't know much about it but what works for me. Unless your TV is something other than device #0? But you say that does work to turn it on, so I don't know...

You can send the "scan" command to list available devices:

pi@retropie:~ $ echo 'scan' | cec-client -s -d 1
opening a connection to the CEC adapter...
requesting CEC bus information ...
CEC bus information
===================
device #0: TV
address:       0.0.0.0
active source: no
vendor:        Vizio
osd string:    TV
CEC version:   1.3a
power status:  on
language:      eng


device #1: Recorder 1
address:       2.0.0.0
active source: no
vendor:        Pulse Eight
osd string:    CECTester
CEC version:   1.4
power status:  on
language:      eng


device #4: Playback 1
address:       1.0.0.0
active source: no
vendor:        Google
osd string:    Chromecast
CEC version:   1.4
power status:  on
language:      ???


currently active source: unknown (-1)

You can also send commands by address instead of device number so in this example, it would be echo 'standby 0.0.0.0' | cec-client -s -d 1.

Retro Arcade Fan

@sleve_mcdichael said in CEC control - Pi turns TV on when booted:

echo 'standby 0.0.0.0' | cec-client -s -d 1

Thanks @sleve_mcdichael. I did try both. It's odd that I can turn it on, but not off. But I've tried both methods. I appreciate the assist though. Maybe someone else will chime in.