Basics of 12pin Port

The ODROID-XU4 provides 12Pin GPIOs.

Easy to use GPIOs
First, you refer to below link.
You check Export number that you want to use GPIO.
Pin description

Create a GPIO file access.
You can access GPIOs using sysfs interface.

echo 34 > /sys/class/gpio/export

Configure the pin direction (in/out)

echo in > /sys/class/gpio/gpio34/direction

Read a value

cat /sys/class/gpio/gpio34/value