Hi,
I have a propblem with configuration of mentioned screen. Screen is working only if I choose PiScreen 3.5 v1 although colours are inverted and also left/right sides of touch screen are registred other way around. Waveshare 3.5b rev2 option in web conf makes nothing (after reboot screen remains all black)… i tried to instal oficial driver for display… without an outcome. Dear zynth club can you help me somehow?
With kind regards
Adrian
I started again with clear install of zynthian added driver and than proceed as descirbed here Another adventure with a generic spi display [Fixed] with partial sucess. UI apeared with OG colours and touchscreen was calibrated nicely, but after few seconds UI went all black. Sometimes terminal load up and after some time disappeared. Touch screen still works and sometimes some parts of screen show up for little moment.
The Waveshare 3.5b rev2 overlay is not working because the current Linux kernel is 4.19.118 and there is no .dtbo overlay file for this display in /boot/overlays.
For kernel versions 4.4 and later, the .dtb overlay file needs to be a .dtbo file.
The fix is simple; copy the .dtb file to .dtbo:
cd /boot/overlays
cp -p waveshare35b-v2-overlay.dtb waveshare35b-v2-overlay.dtbo
Reboot and the display should be ok.
One additional note. I found it necessary to rotate the display and swap the xy coordinates for touch to work correctly. Modify the configuration as shown below:
dtoverlay=waveshare35b-v2-overlay:rotate=270,swapxy=1
One more reboot and Calibrate Touchscreen from the Admin menu and the touch screen should work as expected.
Nigel