Switch between HDMI and Adafruit 2.8" PiTFT - captive touch

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Dollr
 
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Switch between HDMI and Adafruit 2.8" PiTFT - captive touch

Post by Dollr »

Enjoying my new touch screen but would like to also use the GUI on the HDMI at times. Went to the FAQ's and forum search and tried:
FRAMEBUFFER=/dev/fb0 startx &
or
FRAMEBUFFER=/dev/fb1 startx &

FRAMEBUFFER=/dev/fb0 startx & This tries to work. The HDMI screen switches to black with a little white cursor dash in the upper left hand corner. But I get an error dialogue box on the touch screen that stops the process. The error message is:

"GDBus.error:org.freedesktop.PolicyKit1.error.Failed:
An Authentication agent already exists for the given subject"

Also tried:
sudo mv /usr/share/X11/xorg.conf.d/99-fbturbo.conf ~

Get the error message:
mv: cannot stat ` /usr/share/X11/xorg.conf.d/99-fbturbo.conf ‘ : No such file or directory

Hope that info is helpful to someone. Where to go from here? Thanks.

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adafruit_support_mike
 
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Re: Switch between HDMI and Adafruit 2.8" PiTFT - captive to

Post by adafruit_support_mike »

The PolicyKit error means you're trying to run two instances of the GUI on the same machine for the same user. You can fix the problem using the instructions in this post: http://forums.adafruit.com/viewtopic.ph ... 53#p289053

The "no file" error for the 99-fbturbo.conf file means there was no file to move, and can be ignored.

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Dollr
 
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Re: Switch between HDMI and Adafruit 2.8" PiTFT - captive to

Post by Dollr »

Thanks Mike, I'm not seeing "Desktop Session Settings pane" under my preferences. The closest I find is under window settings a check box next to "Show a notification when switching desktops." Tried that with no results. Can't find "PolicyKit AuthenticationAgent" to uncheck. Maybe I'm looking in the wrong place or have a different OS? I'm using Raspian "Wheezy" preinstalled on a card from you guys. Can I do this through the terminal instead maybe? Sorry I'm a bit new using the PI.
Richard
<edit update>
Been searching the internet and tried this. Editing this file by adding LXDE to this line "NotShowIn=GNOME;KDE;LXDE" in this file.
sudo nano /etc/xdg/autostart/lxpolkit.desktop
All it does is stop the error dialog box from opening. Still can't get GUI on HDMI

Also tried "pcmanfm --desktop-pref" to open pref window. Window has no checkbox for "PolicyKit AuthenticationAgent" to uncheck.
Not sure what to do now.
All suggestions are very welcome.
Richard

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adafruit_support_mike
 
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Re: Switch between HDMI and Adafruit 2.8" PiTFT - captive to

Post by adafruit_support_mike »

Oh lovely.. they've changed the interface.

Open a terminal and enter:

Code: Select all

lxession-edit
That will bring up a prefereneces pane for "Automatically Started Applications" which has the PolicyKit control.

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Dollr
 
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Re: Switch between HDMI and Adafruit 2.8" PiTFT - captive to

Post by Dollr »

OK, I'm having the worst luck with this. I tried your code "lxession-edit" but I think it has a typo. I used "lxsession-edit" and it opens the window. Policy kit check-box was already unchecked! Maybe because of the code I edited earlier? Anyway, back to square one which is:

FRAMEBUFFER=/dev/fb0 startx & This tries to work. The HDMI screen switches to black with a little white cursor dash in the upper left hand corner. Then…nothing.
At least the PolicyKit error is no longer displayed.

I know that the HDMI is connected because when I boot the Pi the start-up processes are displayed on the HDMI screen until the PiTFT screen starts up. Then the HDMI screen freezes until I try to switch then the HDMI screen switches to black with a little white cursor dash in the upper left hand corner, it just won't go further.

I appreciate all the help. Anything else I can try?

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adafruit_support_mike
 
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Re: Switch between HDMI and Adafruit 2.8" PiTFT - captive to

Post by adafruit_support_mike »

Run `raspi-config` and see whether the OS is configured to boot into command line or GUI mode. If it's set for the GUI, swap it over to command line.

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Dollr
 
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Re: Switch between HDMI and Adafruit 2.8" PiTFT - captive to

Post by Dollr »

Thanks Mike, did that a couple of days ago and the PI still begins the startup on the HDMI then that screen freezes and the start up continues on the touch screen. When I try to switch back to HDMI using the FRAMEBUFFER code as before I still get the same results. Maybe when you guys update your kernel extension to work on "Raspian Jessie" and I reinstall perhaps it will solve my troubles? Or? Thanks again.
Richard

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adafruit_support_mike
 
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Re: Switch between HDMI and Adafruit 2.8" PiTFT - captive to

Post by adafruit_support_mike »

If the RasPi is configured to boot to a command line and you're executing `FRAMEBUFFER=/dev/fb0 startx &` to launch an HDMI GUI, it should work.

You might need to try starting again from a clean install.

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