gpio-led.sh #2

#!/bin/bash
# Simple script to light up LEDs using sysfs interface
# Pass in GPIO number as argument (not what is labeled on CHIP)

if [ $# -eq 0 ]
then
    echo "Usage: gpio-led.sh [pin number]"
    exit 1
fi

pinNumber=$1

function setup() {
    if [ ! -d /sys/class/gpio/gpio$pinNumber ] 
    then
        sudo sh -c "echo $pinNumber > /sys/class/gpio/export"
        sudo sh -c "echo out > /sys/class/gpio/gpio$pinNumber/direction"
    fi
}

function cleanup() {
    if [ -d /sys/class/gpio/gpio$pinNumber ]
    then 
        sudo sh -c "echo $pinNumber > /sys/class/gpio/unexport"
    fi
}

function dash() {
    sudo sh -c "echo 1 > /sys/class/gpio/gpio$pinNumber/value"
    sleep 1
    sudo sh -c "echo 0 > /sys/class/gpio/gpio$pinNumber/value"
}

function dot() {
    sudo sh -c "echo 1 > /sys/class/gpio/gpio$pinNumber/value"
    sleep .1
    sudo sh -c "echo 0 > /sys/class/gpio/gpio$pinNumber/value"
}

# Example 
setup
dash
dot
cleanup