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connecting R Pi to a usb port on a monitor or projector?

Former Member

We're looking to initially use the Pi as part of our campus emergency notification strategy by having the unit always on and displaying a static message.  We've been able to run the Pi by connecting it to the usb port of several monitors and projectors.  Will regularly powering on and off the monitor/projector will be creating a potential problem for the Pi?

Parents

  • I think I have more questions than answers:

     

    1. What is the purpose of connecting the RPi to the projector/monitor? Is it to transfer data or is it just for power?
    2. If this is going to be part of an emergency notification system that should always be ON, how is it that you are worried about exessive power cycling?

     

    Thanks, Salvador

Reply

  • I think I have more questions than answers:

     

    1. What is the purpose of connecting the RPi to the projector/monitor? Is it to transfer data or is it just for power?
    2. If this is going to be part of an emergency notification system that should always be ON, how is it that you are worried about exessive power cycling?

     

    Thanks, Salvador

Children
  • in reply to SGarciaV

    Classroom projectors/displays are never left on when there is no class in the room.  Faculty are instructed to turn off the projectors/displays after every class. We're planning to connect the video output of the Pi to a spare input on the displays and use the room control system to trigger either switching the video source or turning on the display then switching.  Initially we'll have the Pi put out a static message alerting viewers that there is an emergency.  Ultimately we hope to write a script that would capture the text from our emergency alert system and display that info on the display. 

  • in reply to Former Member

    Thanks Doug. I see now. The USB is mostly for power and the video is to display the message. There are devices out there now that have Linux and are safe to turn ON and OFF at any time. One such device that I can think of is the Insignia Infocast 3.5". You can Google the phrase embedded linux for more specifics on this.

     

    Also, making note of the list of OSes that have been ported to the RPI I have no doubt that you'll be able to configure any one of them in such a way as to avoid the possible pitfall of data corruption due to turning the device OFF at an un expected time. Perhaps one design decision will to selectthe most appropriate OS/distribution for this project. Hopefully some one with this knowledge will chime in. Regards, Salvador