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On a pi B with raspbian-stretch, I have tried every tip I could find to get the touch screen to rotate 180 degrees: commands in config.txt, new drivers, using ./LCD-show 180, and more. Nothing works except modifying the config command to Dtoverlay=tft35a:rotate=270.

However the touch functionality doesn't rotate along with the display.

Can anybody offer me a solution or, worst case, suggest a case that incorporates the display with the usb and ethernet ports on the right? I bought the very nice Astroprint case that puts the screen at a 45 degree angle.

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Add to config.txt:

lcd_rotate=3

This is presuming the LCD is attached by DSI ribbon cable. That should also rotate the touch coordinates too. 1 = 90° 2 = 180° 3 = 270°

https://www.raspberrypi.org/forums/viewtopic.php?t=166959

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  • The display sits right on the GPIO connector, so this doesn't work. Thanks anyway. – Andy F May 27 '18 at 13:20
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I think the touch part of the screen behaves as a different part (a input device) on top ot the display's output device. So you have currently just rotate the latter not the input

This suggest a similar concept - except the screen is rotated by adding this to /boot/cmdline.txt (you may be able to stick with your existing rotation command, in which case some of these options may need to be different!):

fbtft_device.rotate=X

To actually change the touchscreen orientation, try changing swap_xy=0 to swap_xy=1 in /etc/modules (on the ads7846_device line).

Then follow by running sudo apt-get -y install xinput evtest, and adding this line:

DISPLAY=:0 xinput --set-prop 'ADS7846 Touchscreen' 'Evdev Axis Inversion' 1 0

before the . /etc/X11/Xsession line in /etc/X11/xinit/xinitrc, and rebooting.

Again, you will lily require different parameters (it also suggests 0 1 at the end of the DISPLAY line).

These devices are general purposes when you have got the rotation working, it should help to calibrate the touch-screen as well! - this is also detailed in that article.

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  • Thanks and I read the article. Unfortunately the screen doesn't rotate, and there is no ADS line in 'modules' to change. There is only a single unrelated parameter. – Andy F May 27 '18 at 13:32
  • @AndyF (probably should of checked this in the first place, it usually helps to provide this...) what system image and touchscreen model & version are you using? – Wilf May 27 '18 at 18:26
  • Using Raspbian-stretch, Kumantech 3.5", RPI version. Supposedly, I need to re-calibrate the touch and modify /etc/X11/xorg.conf.d/99-calibration.conf with the coordinates, but that doesn't seem to work. – Andy F May 28 '18 at 19:33

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