Touch screen problem with 15,6" size

[miki81]

Hello,
I use Raspberry Pi and I have problem with touch screen:

First time I bought 14" touch screen from chalk-elec ("http://www.chalk-elec.com/?page_id=1283#!/14-HDMI-interface-LCD-with-capacitive-touchscreen/p/36248806/category=3094861":http://www.chalk-elec.com/?page_id=1283#!/14-HDMI-interface-LCD-with-capacitive-touchscreen/p/36248806/category=3094861). I connected it to Raspberry, run QML application and everything was perfect (without callibration, drivers, tslib plugins etc). Then I bought simple 15,6" LED screen and vandal proof touchpanel from CJTouch (exacly this one: "http://www.cjtouch.com/product-show.asp?id=688":http://www.cjtouch.com/product-show.asp?id=688). I calibrated touchpanel in xinput_calibrator application and in X11 server everything works perfect but I have problem with my QML application. The maximum cursor position in X dirrection is about 10 inch and Y maximym position is about 5.18 inch (25,5cm x 13cm) - the touchpanel is 13,58x7,67 inch (34,5x19,5cm). When I slide finger, cursor smoothly moves to the right, left top and down but in limited dimension. What should I do to make everything worked fine? In this forum I read about tslib, it is necessary? Why I did not have to use this plugin to 14" touch screen? I would be grateful for any suggestion

[SGaist]

Hi and welcome to devnet,

It depends on how your touchscreen identifies itself, some of them simply connect connects as mouse input.

When you are saying you have a problem with your QML application, do you mean as a standalone application without X11 running ?

[miki81]

hi, thanks for reply.
The 14" touch screen have USB cable directly from LVDS connector. The 15.6" touch panel have a box with USB cable. When I connect the 15.6" I have /dev/input/event2 and /dev/input/mouse0 device
@
I: Bus=0003 Vendor=24b8 Product=0001 Version=0110
N: Name="HID 24b8:0001"
P: Phys=usb-bcm2708_usb-1.3.2/input0
S: Sysfs=/devices/platform/bcm2708_usb/usb1/1-1/1-1.3/1-1.3.2/1-1.3.2:1.0/input/input2
U: Uniq=
H: Handlers=mouse0 js0 event2
B: PROP=0
B: EV=1b
B: KEY=70000 0 0 0 0 0 0 0 0
B: ABS=100 3
B: MSC=10
@

Yes I running my QML application without X11 server.

[SGaist]

Did you check that your application has the same size as the touchscreen ? I mean pixel size

[miki81]

I solved my problem by the weekend by another method. I reinstall Qt with tslib, calibrate screen by ts_calibrate on my raspberry and run aplication with "-plugin Tslib:/dev/input/event2" parameter. Works OK.

Now I wondering how to hide mouse cursor :)

[FreddeB]

Hi,

You hide the cursor easily by setting the environment variable like..

export QT_QPA_EGLFS_HIDECURSOR=1

Regards
Fredrik