ds18b20.py

#!/usr/bin/python3
# Copyright 2016 Keith Ellis
#
#   Licensed under the Apache License, Version 2.0 (the "License");
#   you may not use this file except in compliance with the License.
#   You may obtain a copy of the License at
#
#       http://www.apache.org/licenses/LICENSE-2.0
#
#   Unless required by applicable law or agreed to in writing, software
#   distributed under the License is distributed on an "AS IS" BASIS,
#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#   See the License for the specific language governing permissions and
#   limitations under the License.
# 

ext_id = "28-041591f7d8ff"
int_id = "28-0015220d64ee"

def gettemp(id):
  try:
    mytemp = ''
    filename = 'w1_slave'
    f = open('/sys/bus/w1/devices/' + id + '/' + filename, 'r')
    line = f.readline() # read 1st line
    crc = line.rsplit(' ',1)
    crc = crc[1].replace('\n', '')
    if crc=='YES':
      line = f.readline() # read 2nd line
      mytemp = line.rsplit('t=',1)
    else:
      mytemp = 99999
    f.close()

    return (int(mytemp[1])/float(1000))

  except:
    return 99999

if __name__ == '__main__':

  # Script has been called directly
  id = ext_id
  print("Temp : " + '{:.1f}'.format(gettemp(id)/float(1000)))