This version of WiringPi-Ruby is EOL, Please see: https://github.com/WiringPi/WiringPi-Ruby

WiringPi: An implementation of most of the Arduino Wiring functions for the Raspberry Pi

WiringPiGem: The WiringPi library wrapped up for Ruby with some OO goodness, sanity checking and other handy additions.

WiringPi GPIO:

require 'wiringpi'
io = WiringPi::GPIO.new
io.write(pin,value)
io.read(pin,value)

Shift out:

io.write(latch_pin, LOW)
io.shiftOut(data_pin, clock_pin, LSBFIRST or MSBFIRST, value)
io.write(latch_pin, HIGH)

Shift out an array of 1/0s (always uses LSBFIRST):

io.shiftOutArray(data_pin, clock_pin, latch_pin, [0,1,0,0,1,1,1,0])

WiringPi GPIO with /sys/class/gpio:

require 'wiringpi
io = WiringPi::GPIO.new(WPI_MODE_SYS)
# read/write/shift as usual

WiringPi Serial:

require 'wiringpi' s = WiringPi::Serial.new('/dev/ttyAMA0',9600) s.serialPuts('Hello world!') s.serialClose

Full details at: https://projects.drogon.net/raspberry-pi/wiringpi/