/etc/init.d/rc.local :
makes it to start as a level "service" whereas,


/etc/rc.local
would simply launch that script at boot time.

- 앞으로 재미난 프로젝트 할 거리가 많아졌다.

Everything in /etc/rc.local runs as the root user.

Also, you can group commands together using ().

The following should work in /etc/rc.local

(sleep 10;python scriptname.py)&

The best way to execute this code is using a callback function. This is a function that is attached to a specific GPIO pin and run whenever that edge is detected. Let’s try one:

import RPi.GPIO as GPIO

GPIO.setmode(GPIO.BCM)

GPIO.setup(23, GPIO.IN, pull_up_down = GPIO.PUD_DOWN)

GPIO.setup(24, GPIO.IN, pull_up_down = GPIO.PUD_UP)

def printFunction(channel):

    print(“Button 1 pressed!”)

    print(“Note how the bouncetime affects the button press”)

GPIO.add_event_detect(23, GPIO.RISING, callback=printFunction, bouncetime=300)

while True:

    GPIO.wait_for_edge(24, GPIO.FALLING)

    print(“Button 2 Pressed”)

    GPIO.wait_for_edge(24, GPIO.RISING)

    print(“Button 2 Released”)

GPIO.cleanup()

Installing Node on a Raspberry PI used to be a whole lot of pain. Compiling an codebase that big on the Pi really taxes the system, plus the usual dependency challenges of native C code. Fortunately, the good chaps at nodejs.org have started automatically building Node for Linux arm Raspberry Pi. This makes life so much easier. Now we can install node in less that five minutes. Here’s how.