I’m using the BBB to play video’s, but after a couple minutes with no mouse or keyboard activity, the screen goes blank. There isn’t a mouse or keyboard plugged into it, so I’m wondering if there is a way to remote SSH onto the machine and re-activate the screen - or ideally stop this from happening. Anyone know how?
I’ve tried setterm -blank poke and -blank 0
I’ve tried sending code to /dev/tty0
I’ve tried xdotool to move the mouse, but it says no display is found
The guidance I received was to try the setterm stuff you tried. I had not gotten around to trying it myself, so it is depressing for me that it did not work for you.
I tried xdotool also. I think that tool is only going to work on x-session displays, and it is not clear that the emulated mouse movement would occur at a primitive enough driver level to wake up hardware if that was attempted in an X-environment anyway.
I’d really like to see an answer on this one. We keep trying to do wild stuff with the BBB, and sometimes they are un-attainable because we have not reminded ourselves that the hardware is targeted more at the embedded world than the desk-top world. Yet, this issue deals with desk-top like behavior interfering with behavior that is desired for embedded applications.
It would be good to find out, at least, what software system is in charge of this behavior. It does not appear to be Gnome, because I tried mucking with the display sleep settings there too.
I have had no luck in getting the HDMI to wake back up after it shuts off. But, if you want to disable the DPMS functionality that shuts it off in the first place, add “consoleblank=0” to your kernel command line arguments in the uEnv.txt.
Interestingly, my display goes into blanking *INSTANTLY* after boot if
I do not have a keyboard plugged in. Unblanking the display via the
above echo brings the display to life. Setting the consoleblank=0 on
the kernel command line only affects text consoles, not the GUI.
If you use the native BeagleBone gui to disable the power management
turning off the monitor, the display will come up regardless of
whether or not you have a KB/Mouse connected. There's probably a
gnome config file somewhere that you could edit to disable blanking
via the command line, but I don't know the guts of gnome well enough
to know what it would be.
Thanks all for your suggestions… Just tried the echo suggestion above and it did indeed work. So I guess if I need to keep my video playing on screen I can just have a script execute that line on a timer. Not the prettiest solution, but it works!
The only other thing I’ve actually had luck with to get the gnome desktop to come back up is to actually kill it (killall gnome-session) which literally ends and restarts gnome, resulting in the monitor coming back to life.