gpio

General Purpuse Input Output pins, found on many SBC devices.

9front / plan9 provide GPIO support for some devices, eg. Raspberry Pi.

usage

Quick reference for working with gpio pins.

• mount gpio:

  bind -a '#G' /dev
  

• read pin state:

  cat /dev/gpio/GPIO0
  

• write pin state:

  echo 1 > /dev/gpio/GPIO0
  echo 0 > /dev/gpio/GPIO0
  

• select pin function (rpi):

  echo func out > /dev/gpio/board/GPIO0
  

  (possible functions are: "in", "out", "f5", "f4", "f0", "f1", "f2", "f3”)

• select pin pull state (rpi):

  echo pull up > /dev/gpio/board/GPIO0
  

  (possible pull states are: "off", "down", "up”)

Raspberry Pi 1

• pinout