Tuesday, December 13, 2016

Screen Blanking On Raspberry Pi With Official Touch Screen

On the official RPi touch screen the screen goes blank after 30 minutes, and at first glance this seemed to do what I spent a lot of time scripting for an HDMI screen.

However, I noticed that using this default screen blanking the touch which unblanks the screen also gets sent to whatever program is below it, so if you happen to touch a button on the 'blank' screen, the button gets a press event.

So, in order to fix this I installed the xscreensaver
sudo apt-get install xscreensaver
and then configure it using
which allows me to set it to a black screen, and I also noticed there is the option there to have it activate the power management of the screen to turn it off. For this application I want the screen to go off after 1 minute, so I set that, and very easily I have the functionality I need.

The screen goes off after 1 minute, and any touch instantly brings the screen on, but doesn't get passed through to the underlying application. Perfect.

I also removed the default screen blanking, as I suspect there is a bit of an issue sometimes
edit /etc/lightdm/lightdm.conf
xserver-command=X -s 0 -dpms

 Credit: http://www.geeks3d.com/hacklab/20160108/how-to-disable-the-blank-screen-on-raspberry-pi-raspbian/

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