#!/usr/bin/python
# Initialisierung
import RPi.GPIO as GPIO
import time
import os
GPIO.setmode(GPIO.BCM)
 
# Hier den entsprechden GPIO-PIN auswaehlen
GPIO_TPIN = 24
 
print "Sicheres Herunterfahren bei Stromausfall (CTRL-C zum Schliessen)"
 
# Set pin as input
GPIO.setup(GPIO_TPIN,GPIO.IN)      
 
Current_State  = 0
Previous_State = 0
 
try:
 
  print "Warte auf Initialisierung der Spannungsversorgung..."
 
  
  while GPIO.input(GPIO_TPIN)==1:
    Current_State  = 0
 
  print "  Bereit"
 

  while True :
 
    Current_State = GPIO.input(GPIO_TPIN)
 
    if Current_State==1 and Previous_State==0:
      Previous_State=1
      os.system("sudo shutdown -h now")
    elif Current_State==0 and Previous_State==1:
      Previous_State=0
 
    time.sleep(0.01)
 
except KeyboardInterrupt:
  print "  Quit"
  GPIO.cleanup()