Is it possible to control GPIOD_15 (pin 39) on VIM4? I have tried controlling GPIOT_15 (GPIOD_15 does not seem to be present) using the method described here: GPIO | Khadas Documentation, but this does not work (voltage is always 3.1 VDC).
Yes you can control pin with wiringpi library or direct via gpio commands: sudo gpio mode 18 out // this will open GPIOD_15 pin39 as output sudi gpio write 18 1 // sets logical 1 sudi gpio write 18 0 // sets logical 0