LS-AE-Raspi-2 Aufgabe 1.2

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

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

interval = 10
prev_temp = 0
sensor = None
DHT_PIN = None
LED_BLUE = None
LED_RED = None

def initialize():
  global sensor, DHT_PIN, LED_BLUE, LED_RED

  DHT_PIN = 26
  LED_BLUE = 21
  LED_RED = 20

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

  sensor = Adafruit_DHT.DHT11

def destroy():
  GPIO.cleanup()
  sys.exit()

def getTime():
  curDT = datetime.now()
  curDT = curDT.strftime("%Y-%m-%d %H:%M:%S")
  return curDT

def measure():
  timestamp = getTime()
  humidity, temperature = Adafruit_DHT.read_retry(sensor, DHT_PIN)

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

  print("Time: {} | " +
    "Temperature: {} °C | " +
    "Humidity: {} %".format(
      timestamp, temperature, humidity))

  return temperature

def loop():
  global prev_temp

  while (True):
    prev_temp = measure()
    sleep(interval)

if (__name__ == '__main__'):
  print("Press CTRL-C to exit.")
  initialize()

  try:
    loop()
  except (KeyboardInterrupt):
    print("Exiting")
    destroy()