I'm trying to blink an LED connected to the GPIO pins of my Dragonboard, on linux.
I logged as root by sudo -i, entered the /sys/class/gpio folder, and did "echo 938 > export", to access my LED which is on the pin 23.
The command doesn't work and the output is "-bash: echo: write error: Invalid argument
Is the command wrong? How can I access the pins? Thanks.