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According to the manual from Joy-it (cannot find an english version) I should download the latest firmware and use modprobe to load the kernel module but I receive an error message that the kernel module does not exist.

What I did:

sudo REPO_URI=https://github.com/notro/rpi-firmware rpi-update

sudo reboot

sudo modprobe ads7846_device verbose=2 cs=1 speed=2000000 model=7843 x_min=300 x_max=3800 y_min=700 y_max=3400 x_plate_ohms=60 pressure_max=255 gpio_pendown=17 keep_vref_on=1 swap_xy=1

And I got the error that ads7846_device does not exist.

So I followed this post on github:

I could not compile the ads7846-overlay.dts file due to an error:

sudo dtc -@ -I dts -O dtb -o ads7846-overlay.dtb ads7846-overlay.dts FATAL ERROR: Unable to parse input tree

However the ads7846-overlay.dtb file is already present in /boot/overlays

So I edited the /boot/config.txt file accordingly:

# enable the 3.2 " TFT screen dtdebug=1 device_tree=ads7846-overlay.dtb dtoverlay=ads7846,cs=1,speed=2000000,model=7843,xmin=300,xmax=3800,ymin=700,ymax=3400,x_plate_ohms=60,pressure_max=255,gpio_pendown=17,keep_vref_on=1,swap_xy

However, sudo vcdbg log msg | grep Loading gives me following error:

`001335.223: Failed to load overlay 'ads7846'

What I haven`t even tried yet is to load the overlay for the fbtft module (sainsmart32). Any ideas what might cause the error ?

1

In case someone has the same issue: The correct manual can be downloaded from this link.

Basically, it is a waveshare device:

Modify config.txt:

dtparam=spi=on dtoverlay=waveshare32b :rotate=270

Add fbcon=map:10 to the end of the first line in /boot/cmdline.txt

Create sudo nano /usr/share/X11/xorg.conf.d/99-calibration.conf and add

Section "InputClass" Identifier "calibration" MatchProduct "ADS7846 Touchscreen" Option "Calibration" "160 3723 3896 181" Option "SwapAxes" "1" EndSection

Change fb0 to fb1 in /usr/share/X11/xorg.conf.d/99-fbturbo.conf (change of output from HDMI to the Display)

Clone git clone https://github.com/swkim01/waveshare-dtoverlays.git and copy all .dtb files to /boot/overlays

Get the latest drivers sudo REPO_URI=https://github.com/notro/rpi-firmware rpi-update

Afterwards you just have to enable autologon with raspi-config

Screen is working. Touch feature not yet. Just found this tutorial which describes the whole process in english.

0

The line device_tree=ads7846-overlay.dtb appears to be wrong.

Try removing that line.

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