thermometer.py

import os
import glob
import time
import RPi.GPIO as GPIO
import json
from datetime import datetime
from firebase import firebase

os.system('modprobe w1-gpio')
os.system('modprobe w1-therm')

import requests.packages.urllib3

firebase = firebase.FirebaseApplication('https://iot-homebrew.firebaseio.com', None)

base_dir = '/sys/bus/w1/devices/'
device_folder = glob.glob(base_dir + '28*')[0]
device_file = device_folder + '/w1_slave'

on_pin = 24
on_pin2 = 26

GPIO.setmode(GPIO.BOARD)
GPIO.setup(on_pin, GPIO.OUT)
GPIO.setup(on_pin2, GPIO.OUT)

override = 0
desired_temp = 0
hysteresis = 0.5
extra_resistor_cutoff_temp = 5
power_is_on = False
first_resistor_power_on = False
second_resistor_power_on = False
get_current_program_interval = 5
current_program = {}
current_step_id = {}

content_type = {'X_CONTENT_TYPE': 'application/json'}

def read_temp_raw():
	f = open(device_file, 'r')
	lines = f.readlines()
	f.close()
	return lines

def power_on():
	print('FULL POWER')
	power_on_first_resistor()
	power_on_second_resistor()

def power_on_first_resistor():
	print('First resistor on')
	global power_is_on
	global first_resistor_power_on

	first_resistor_power_on = True

	GPIO.output(on_pin, False)

	if power_is_on == False
		power_is_on = True
		post_power(power_is_on)

def power_on_second_resistor():
	print('Second resistor on')
	global power_is_on
	global second_resistor_power_on

	second_resistor_power_on = True

	GPIO.output(on_pin2, False)

	if power_is_on == False
		power_is_on = True
		post_power(power_is_on)

def power_off():
	print('Virta pois')
	global power_is_on
	global first_resistor_power_on
	global second_resistor_power_on

	power_is_on = False
	first_resistor_power_on = False
	second_resistor_power_on = False

	GPIO.output(on_pin, True)
	GPIO.output(on_pin2, True)

	post_power(power_is_on)

def power_off_second_resistor():
	print('Second resistor off')
	global second_resistor_power_on

	second_resistor_power_on = False
	GPIO.output(on_pin2, True)

def read_temp():
	lines = read_temp_raw()

	while lines[0].strip()[-3:] != 'YES':
		time.sleep(0.2)
		lines = read_temp_raw()

	equals_pos = lines[1].find('t=')

	if equals_pos != -1:
		temp_string = lines[1][equals_pos+2:]
		temp = float(temp_string) / 1000.0
		return temp

def post_temp(current_temp):
	global content_type
	temp_info = {"timestamp": time.time(), "temp": current_temp, "desiredTemp": desired_temp, "step": current_step_id}
	firebase.post(url='/Temperatures', data=temp_info, headers=content_type)

def post_power(power):
	global content_type
	firebase.put('/Power', "timestamp", time.time())
	firebase.put('/Power', "state", power)

def get_current_program():
	global desired_temp
	global current_program
	current_program = firebase.get('/CurrentStep', None)

def get_override():
	global override
	power = firebase.get('/Power', None)
	override = power["override"]

def get_desired_temp():
	if current_program != None:
		return float(current_program["temp"])
	return 0

def set_auto_power(current_temp, desired_temp):
	first_resistor_power_off_temp = desired_temp - hysteresis
	second_resistor_power_off_temp = first_resistor_power_off_temp - extra_resistor_cutoff_temp

	if current_temp > first_resistor_power_off_temp and power_is_on == True:
		power_off()
	elif current_temp > second_resistor_power_off_temp and second_resistor_power_on == True:
		power_off_second_resistor()
	elif current_temp < second_resistor_power_off_temp and second_resistor_power_on == False:
		power_on()
	elif current_temp < first_resistor_power_off_temp and first_resistor_power_on == False:
		power_on_first_resistor()

# Set initial state
power_off()

# Run program
print('Aloitetaan')
print('Laitefilu: ' + device_file)
loops = 0
while True:

	if loops == 0:
		get_current_program()
		loops = get_current_program_interval
	loops = loops - 1

	current_temp = read_temp()
	desired_temp = get_desired_temp()

	print("desired temp: " + str(desired_temp) + ", current temp: " + str(current_temp))

	post_temp(current_temp)

	# Override
	get_override()
	if override == 1:
		power_off()
	elif override == 2:
		power_on()
	else:
		override = 0

	# Automatic
	if override != 0:
		print("Overrided " + str(override))
	else
		set_auto_power(current_temp, desired_temp)

	time.sleep(1)