touch screen problem

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MKrohn
 
Posts: 9
Joined: Fri Jul 04, 2014 6:14 pm

touch screen problem

Post by MKrohn »

Hi

I just got my PiTFT (PID 1601)

I went through the install proceedure

after entering the:

sudo modprobe spi-bcm2708
sudo modprobe fbtft_device name=adafruitts rotate=90
export FRAMEBUFFER=/dev/fb1
startx

The console screen goes from white to black and then comes back on as the directions say but
I get an error code window:

Error
GDBus, Error:org.freedesktop,PolicyKit1.Error,Failed:An
authentication agent already exists for the given subject

and the PiTFT is a not-too-bright solid gray

the Pi is running on a new version of NOOBS from Adafruit

eta it is a B+ Pi

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adafruit_support_mike
 
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Joined: Thu Feb 11, 2010 2:51 pm

Re: touch screen problem

Post by adafruit_support_mike »

The error means you're running another desktop for the same user on another display.

PolicyKit is a feature of LXDE (the desktop manager) that restricts access to things like the GPIO pins. You can shut it off by pulling up the Preferences -> Desktop Settings pane and unchecking "Authentication Agent". Restart the RasPi after that and the error should go away.

MKrohn
 
Posts: 9
Joined: Fri Jul 04, 2014 6:14 pm

Re: touch screen problem

Post by MKrohn »

Yes I found that on another forum and unchecking it in preferences works

but the TFT still does not work properly

I now get a screen on the tft but it is now saying near the end of the boot up:

27.041632] fbtft_device: missing module parameter: 'name'

This shows up after entering:

"Module Auto-loading

We'll now make the modules auto-load. Lets edit the /etc/modules list with

sudo nano /etc/modules

add two lines

spi-bcm2708
fbtft_device <---- is this a typo in the detailed installation -- there is no 'name' parameter

Then Control-X Y [return] to save <-- and this is confusing and needs to be rewritten (IMO)


I am going to try the easy install

does adafruit plan to offer a NOOBS micro sd chip with the tft files loaded ? I would buy one

MKrohn
 
Posts: 9
Joined: Fri Jul 04, 2014 6:14 pm

Re: touch screen problem

Post by MKrohn »

So I did the easy install (and it really is easy thanks)

but this is what is now happening

I reboot, at some point in the reboot the tft displays the start up code but then

the gray screen after the HMDI comes up with the desktop

there is a non flashing 'cursor' line on the display but that's all

did I miss something ? I tried rebooting it with the HDMI unplugged -- still no display after the kernal code

I checked the cmdline.txt

" At the end of the line, find the text that says rootwait and right after that, enter in:
fbcon=map:10 fbcon=font:VGA8x8 then save the file."

and it is OK

MKrohn
 
Posts: 9
Joined: Fri Jul 04, 2014 6:14 pm

Re: touch screen problem

Post by MKrohn »

I went back and ran this

sudo modprobe spi-bcm2708
sudo modprobe fbtft_device name=adafruitts rotate=90
export FRAMEBUFFER=/dev/fb1
startx

and it works

I must have messed something up trying the detailed install

however it seems I have to run the above code after a reboot in order for the display to work

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adafruit_support_mike
 
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Joined: Thu Feb 11, 2010 2:51 pm

Re: touch screen problem

Post by adafruit_support_mike »

You can add those lines to the end of /etc/rc.local to have the system run them as part of the boot process.

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RobotPi
 
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Joined: Tue Sep 16, 2014 11:33 am

Re: touch screen problem

Post by RobotPi »

I have the same problem on a B+.
I installed the software following the instructions for the kernel (the existing image takes too long to discard).
I have tried the above fix but that causes the HDMI monitor to black out (bar a brief small display of rainbow like box in top right of screen) and the Touchscreen to remain grey small pixels. There is no other display on the touchscreen but it is responding to styluses on the configuration tests (but not displaying any image)

Even in the mid-gray pixel mode it does respond to the mouse

Any suggestions?

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RobotPi
 
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Joined: Tue Sep 16, 2014 11:33 am

Re: touch screen problem

Post by RobotPi »

So no response on this issue.
So I reflashed a micro-sd card with the recommended image (https://learn.adafruit.com/adafruit-pit ... sy-install ).

This causes the B+ to halt in the pi startup script at the point where the B+ is configuring the touchscreen device!

MKrohn
 
Posts: 9
Joined: Fri Jul 04, 2014 6:14 pm

Re: touch screen problem

Post by MKrohn »

This is starting to sound like a B+ bug to me

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RobotPi
 
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Joined: Tue Sep 16, 2014 11:33 am

Re: touch screen problem

Post by RobotPi »

We tried another Touchscreen with success - this is using our existing Rasbian image with the kernel extension for the TS.
We can swap between HDMI and touchscreen and use the two buttons for power and Pi reboot
Good news except
- the MicroSD image linked above still hangs.

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