1#!/usr/bin/python
2# Author: Jon Trulson <jtrulson@ics.com>
3# Copyright (c) 2015 Intel Corporation.
4#
5# Permission is hereby granted, free of charge, to any person obtaining
6# a copy of this software and associated documentation files (the
7# "Software"), to deal in the Software without restriction, including
8# without limitation the rights to use, copy, modify, merge, publish,
9# distribute, sublicense, and/or sell copies of the Software, and to
10# permit persons to whom the Software is furnished to do so, subject to
11# the following conditions:
12#
13# The above copyright notice and this permission notice shall be
14# included in all copies or substantial portions of the Software.
15#
16# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23
24import time, sys, signal, atexit
25import pyupm_mg811 as sensorObj
26
27# Instantiate an MG811 on analog pin A0, and digital pin D2 with an
28# analog reference voltage of MG811_AREF (5.0)
29
30sensor = sensorObj.MG811(0, 2, 5.0)
31
32## Exit handlers ##
33# This function stops python from printing a stacktrace when you hit control-C
34def SIGINTHandler(signum, frame):
35	raise SystemExit
36
37# This function lets you run code on exit
38def exitHandler():
39	print "Exiting"
40	sys.exit(0)
41
42# Register exit handlers
43atexit.register(exitHandler)
44signal.signal(signal.SIGINT, SIGINTHandler)
45
46# Every tenth of a second, sample the sensor and output it's
47# detected CO2 concentration in parts per million (ppm)
48
49while (1):
50        print "CO2 concentration in PPM: ", sensor.ppm()
51	time.sleep(.1)
52