Waveshare '4A only GPIO touchscreen

Lanfranco · December 21, 2022, 12:54pm

HI, I’ve now mounted this display, with the Webconf drivers it works but the touchscreen doesn’t work… I don’t use it, but I would like to know if it’s normal or if I’m doing something wrong… Thanks as always

le51 · December 22, 2022, 1:12pm

Can you provide:

content of /var/log/Xorg.0.log file
content of /boot/config.txt file
output of dmesg command

Lanfranco · December 22, 2022, 2:44pm

I’ll try as soon as possible… thanks

I’m obviously not an expert in linux, but normally by inserting the SD into the PC I was able to read at least the .txt configuration file… Win10 doesn’t open the SD… I’m sorry but I have posted screenshots…
Files.rar (4.0 MB)

le51 · December 24, 2022, 4:52pm

Hi @Lanfranco ,

form Xorg.0.log:

[ 6.239] (II) config/udev: Adding input device ADS7846 Touchscreen (/dev/input/mouse0)
[ 6.239] (II) No input driver specified, ignoring this device.
[ 6.239] (II) This device may have been added with another device file.

the touchscreen device driver isn’t correctly loaded.

Waveshare provide a tool to setup this display:

For your display, it’s this script:

github.com

waveshare/LCD-show/blob/master/LCD4-show

i=1
for lines in `cat ./boot/mark`
do
  case ${i} in
  1) var1=${lines};;
  esac
  i=`expr ${i} + 1`
done
#echo "$var1"

j=$(uname -n)
if test "$var1" = "0" -a "$1" != "lite" -a "$2" != "lite" ;then

if test "$j" != "retropie" ;then
sudo apt-get install xserver-xorg-input-evdev
sudo cp -rf /usr/share/X11/xorg.conf.d/10-evdev.conf /usr/share/X11/xorg.conf.d/45-evdev.conf
fi

if test "$j" = "retropie" ;then
sudo cp -rf ./nes /home/pi/RetroPie/roms/

This file has been truncated. show original

DO NOT RUN THIS SCRIPT, it will create a big mess in the Zynthian setup.

But copy this file:

github.com

waveshare/LCD-show/blob/master/usr/share/X11/xorg.conf.d/45-evdev.conf

#
# Catch-all evdev loader for udev-based systems
# We don't simply match on any device since that also adds accelerometers
# and other devices that we don't really want to use. The list below
# matches everything but joysticks.

Section "InputClass"
        Identifier "evdev pointer catchall"
        MatchIsPointer "on"
        MatchDevicePath "/dev/input/event*"
        Driver "evdev"
EndSection

Section "InputClass"
        Identifier "evdev keyboard catchall"
        MatchIsKeyboard "on"
        MatchDevicePath "/dev/input/event*"
        Driver "evdev"
EndSection

This file has been truncated. show original

in /usr/share/X11/xorg.conf/10-evdev.conf

And :

github.com

waveshare/LCD-show/blob/master/usr/share/X11/xorg.conf.d/99-fbturbo.conf

# This is a minimal sample config file, which can be copied to
# /etc/X11/xorg.conf in order to make the Xorg server pick up
# and load xf86-video-fbturbo driver installed in the system.
#
# When troubleshooting, check /var/log/Xorg.0.log for the debugging
# output and error messages.
#The driver is made by Waveshare&Spotpear
# Run "man fbturbo" to get additional information about the extra
# configuration options for tuning the driver.

Section "Device"
        Identifier      "Allwinner A10/A13 FBDEV"
        Driver          "fbturbo"
        Option          "fbdev" "/dev/fb1"

        Option          "SwapbuffersWait" "true"
EndSection

in /usr/share/X11/xorg.conf.d/99-fbturbo.conf

And:

github.com

waveshare/LCD-show/blob/master/etc/X11/xorg.conf.d/99-calibration.conf-4-90

Section "InputClass"
        Identifier      "calibration"
        MatchProduct    "ADS7846 Touchscreen"
        Option  "Calibration"   "172 3950 3871 194"
        Option  "SwapAxes"      "0"
        Option "EmulateThirdButton" "1"
        Option "EmulateThirdButtonTimeout" "1000"
        Option "EmulateThirdButtonMoveThreshold" "300"
EndSection

in /etc/X11/xorg.conf.d/99-calibration.conf

While /boot/config.txt should looks like this:

dtoverlay=waveshare35a:rotate=90
#dtoverlay=ads7846,cs=1,penirq=17,penirq_pull=2,speed=1000000,keep_vref_on=1,swapxy=0,pmax=255,xohms=60,xmin=200,xmax=3900,ymin=200,ymax=3900
hdmi_force_hotplug=1
#max_usb_current=1
hdmi_group=2
hdmi_mode=1
hdmi_mode=87
hdmi_cvt 480 320 60 6 0 0 0
hdmi_drive=2
display_rotate=1

Lanfranco · December 24, 2022, 5:07pm

Thank you very much… I got scared of everything you wrote… The problem is that I can’t open these files in order to paste the text… If I open from terminal I can paste with ctrl + ? . I also had Ubuntu installed in dual boot, but I had a problem and I will have to install it again…

le51 · December 24, 2022, 5:39pm

If you have a PC running Ubuntu, you will be able to mount the microSD card and do all the manipulations from there with any kind of text editor.

Lanfranco · December 24, 2022, 6:15pm

Great… now I reinstall Ubuntu. You have been very kind. Thank you

/usr/share/X11/xorg.conf/10-evdev.conf
/usr/share/X11/xorg.conf.d/99-fbturbo.conf
these two files were not in the folder. I created and inserted them with sudo mv

/etc/X11/xorg.conf.d/99-calibration.conf
This file was there and I changed it.

… and then I added the lines on the config.txt file

Now I’ll try if it works…

Lanfranco · December 25, 2022, 1:07pm

The display goes dark but no writing appears… I certainly did something wrong…