Remote screen controled by robots. Create a cheap Videoconference, digital signage or dashboard with an old computer or raspberry pi connected to a small or large screen.

You (or your robot) can change the screen content, change vol or Power On or Off with MQTT or HTTP commands.

You can use these commands:

• goto url Where url is where the page it ́s going to load
• tv on
• tv off
• mute on
• mute off
• vol +
• vol -
• vol (0-10)

You are going to need a computer with a screen.

• PC. You ca use linux (prefered) or windows. I didn ́t check a Apple but you can try.
• Raspberry Pi, or may be Orange Pi or Banana or any fruit. I test with a Rpi 4 & 400, but a Zero Wifi may be a cheap and good option.

• Computer screen
• TV. I test this one, with the internal HDMI-CEC protocol, and is the best solution. It ́s big, cheap and it works with and USB camera like a videoconference system without any contact (COVID Free). If you want to use it with a raspbery pi (or an ARM processor)

sudo apt install chromium-browser chromium-codecs-ffmpeg
sudo apt install cec-utils
sudo apt install npm
md roboard
cd roboard
npm i roboard
npm install

edit the file: /etc/xdg/lxsession/LXDE/autostart comment out a xscreensaver command, and add these xset lines

#@xscreensaver -no-splash
@xset s off
@xset -dpms
@xset s noblank

node roboard.js

First time you are going to write this information:

• company name (only to help for creating the topics) no spaces or special caracters.
• device name: no spaces or special caracters.
• splasUrl: The default url for the screen. Please write http:// or https://.
• mqtt server: Begin with mqtt:// the domain, and finish with : and port number only if is different to 1883.
• infotopic: The topic you are going to use to know how is working, suscribe it.
• commandtopic: The topic you are going to use to send commands, publish in there.

Edit config.js to configure how the chromium works only if you want to change something. Remember to do not use the root user to activate the roboard application.

To do this, it leverages the great work of:

• cec-monitor by Pablo González of Senzil.
• libcec by PulseEight.
• hdmi-cec.
• node-cec
• MQTT.
• Puppeteer
• prompt-sync from David Mark Clements.