Using sysfs to Debug

Follow the procedure below to perform the debug.
  1. Enter the /sys/class/gpio/...(sysfs interface) menu.

    Figure 1. Using sysfs to Debug
  2. Use the following commands to run the debug.
    # cd /sys/class/gpio/ 
    # ls
    export	gpiochipO	gpiochip64	unexport
    # echo 44 > export		
    # ls			
    export	gpio44	gpiochipO	gpiochip64	unexport
    # cd gpio44/		
    # ls			
    active_low	direction	subsystem	value
    device	edge	uevent	
    # cat direction 
    in
    # cat value
    1