OK, I place the resistor to “ON” on “LED_FUNCTION” , now it allow to control backlight , I follow the trace and it can be controlled with GPIO 22 (which correspond to wiringpi pin number 3).
I’m now able to switch on and off the screen with gpio mode 3 out and then gpio write 3 1 or gpio write 3 0
But I’m not able to manage it with PWM , I tried something like this without success :
gpio -g mode 22 pwm #Set the pin as PWM
gpio pwmc 100
gpio -g pwm 22 0 #Set the brightness to dimmest
gpio -g pwm 22 1023 #Set the brightness to the brightest
gpio -g mode 22 out #Clean the pin
My pwm commands seems to haven’t any effect, I don’t know why…
All GPIO of the RPI 3 are pwm capable ?
Not a big deal if I can’t dimmer the screen , how can I trigger the switch off of the screen at screensaver timeout (in touch display plugin) ?