Simple program that polls X to check if DPMS is enabled and screen is off and turns TFT screens backlight off
Installare dtc
pacman -S dtc
compilare backlight-overlay.dts dopo avere eventualmente cambiato il GPIO pin
dtc -@ -I dts -O dtb -o backlight.dtbo backlight-overlay.dts
copiare backlight.dtbo a /boot/overlay
aggiungere dtoverlay=backlight a /boot/config.txt
compilare backlightd.cpp
g++ backlightd.cpp -lX11 -lXext -o backlightd
copiare backlightd a /usr/bin
aggiungere /usr/bin/backlightd & a /etc/X11/xinit/xinitrc dopo matchbox-window-manager
calibrare schermo
reference URL: https://forums.raspberrypi.com/viewtopic.php?t=201639
http://comfilewiki.co.kr/en/doku.php?id=comfilepi:controlling_the_lcd_backlight:index