Sensoren - DHT11

#!/usr/bin/python
# -*- coding: utf-8 -*-

from datetime import datetime
from time import sleep
from RPi import GPIO
import Adafruit_DHT

sensor = Adafruit_DHT.DHT11
pin = 26
LED_RED = 20
LED_BLUE = 21
delay = 10

def setup():
  GPIO.setwarnings(False)
  GPIO.setmode(GPIO.BCM)
  GPIO.cleanup()
  GPIO.setup(LED_RED, GPIO.OUT)
  GPIO.setup(LED_BLUE, GPIO.OUT)

def destroy():
  GPIO.cleanup()

def loop():
  prev_temp = 0

  while (True):
    ts = datetime.now()
    h, t = Adafruit_DHT.read_retry(sensor, pin)

    if (t < prev_temp):
      GPIO.output(LED_RED, GPIO.LOW)
      GPIO.output(LED_BLUE, GPIO.HIGH)
    elif (t > prev_temp):
      GPIO.output(LED_RED, GPIO.HIGH)
      GPIO.output(LED_BLUE, GPIO.LOW)
    else:
      GPIO.output(LED_RED, GPIO.HIGH)
      GPIO.output(LED_BLUE, GPIO.HIGH)

    prev_temp = t

    print("Zeit: {} Temperatur: {0:0.1f}°C " +
      "Luftfeuchtigkeit: {1:0.1f}%".format(ts, t, h))
    sleep(delay)

if (__name__ == '__main__'):
  setup()
  print "Die Messung erfolgt alle %d Sekunden." % delay
  print 'Programm mit CTRL-C beenden.'
  try:
    loop()
  except (KeyboardInterrupt):
    destroy()