thingspeak_update.py

# -*- coding: utf-8 -*-
#!/usr/bin/python2.7
'''
Title:  ThingSpeak / RaspberryPi Weather station
Author: AndyPi

Hardware:
DHT22 (temp / humidity)
BMP085 (temp/atmospheric pressure)
Shinyei PPD42NS Dust Sensor (air quality)
'''

from __future__ import print_function
import sys
import httplib
import urllib
import time
from collections import deque
import pickle
import DHT22
import pigpio
import Adafruit_BMP.BMP085
import air_quality
from config import *

BMP085sensor = Adafruit_BMP.BMP085.BMP085()

# Setup RPi GPIO pins
PIN_DHT22 = 8
PIN_PPD42NS = 7
#PIN_DHT22i = 7
PIN_BMP085_SDA = 0
PIN_BMP085_SCL = 0
PIN_TGS2600 = 0

def update_thingspeak(data1, data2, data3, data5):
	'''
	update thingspeak routine (max once every 15 seconds)
	'''
	params = urllib.urlencode({"field1": data1, "field2": data2, "field3": data3, "field5": data5, 'key': THINGSPEAK_APIWRITE})
	headers = {"Content-typZZe": "application/x-www-form-urlencoded", "Accept": "text/plain"}
	conn = httplib.HTTPConnection("api.thingspeak.com:80")
	try:
		conn.request("POST", "/update", params, headers)
		#response = conn.getresponse()
		#print response.status, response.reason
		#data = response.read()
		conn.close()
	except:
		pass
		# error handler if needed

def get_current_aqi():
	'''
	Returns the instantaneous AQI from the PPD42NS sensor
	'''
	s = air_quality.sensor(pi, 7) # set the GPIO pin number
	time.sleep(30) # Use 30s for a properly calibrated reading.
	g, r, c = s.read() # get the gpio, ratio and concentration in particles / 0.01 ft3
	concentration_ugm3 = s.pcs_to_ugm3(c) # convert to SI units
	aqi = s.ugm3_to_aqi(concentration_ugm3) # convert SI units to US AQI (instantaneous only)
	return aqi

if __name__ == "__main__":
	'''
	Main program - reads all sensors and sends readings to thingspeak
	'''

	pi = pigpio.pi()

	# Humidity and temp from DHT22 (outisde)
	s = DHT22.sensor(pi, PIN_DHT22, LED=None, power=8)
	s.trigger()
	time.sleep(0.2)
	humidity = s.humidity()
	temp1 = s.temperature()

	# Humidity and temp from DHT22 (inside)
	#si = DHT22.sensor(pi, PIN_DHT22i, LED=None, power=8)
	#si.trigger()
	#time.sleep(0.2)
	#humidityi = si.humidity()

	# temp and pressure from BMP085
	temp2 = BMP085sensor.read_temperature()
	pressure = BMP085sensor.read_pressure()

	# calc average temp of 2 sensors
	temperature = 0
	temperature = (temp1+temp2)/2

	# get reading from air quality sensor
	airq = get_current_aqi()

	try:
		with open('aqireadings.q', 'rb') as qfile:
			q = pickle.load(qfile) # load q
	except:
		q = deque(maxlen=4) # create q if no file exists (first run only)

	q.append(airq) # Append latest reading to start of queue
	aqi_1hour_average = sum(q)/len(q) # calculate average
	with open('aqireadings.q', 'wb') as qfile:
		pickle.dump(q, qfile) # save queue to local file

	update_thingspeak(temperature, humidity, pressure, aqi_1hour_average)
	print("Temp (DHT22): " + str(temp1))
	print("Temp (BMP): " + str(temp2))
	print("Humidity (outide): " + str(humidity))
	#print("Humidity (inside): " + str(humidityi))
	print("Pressure: " + str(pressure))
	print("AQI 1-hour average: " + str(aqi_1hour_average))

	sys.exit()