A little bit messy 
/**
The MySensors Arduino library handles the wireless radio link and protocol
between your home built sensors/actuators and HA controller of choice.
The sensors forms a self healing radio network with optional repeaters. Each
repeater and gateway builds a routing tables in EEPROM which keeps track of the
network topology allowing messages to be routed to nodes.
Created by Henrik Ekblad <henrik.ekblad@mysensors.org>
Copyright (C) 2013-2015 Sensnology AB
Full contributor list: https://github.com/mysensors/Arduino/graphs/contributors
Documentation: http://www.mysensors.org
Support Forum: http://forum.mysensors.org
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
version 2 as published by the Free Software Foundation.
*******************************
REVISION HISTORY
Version 1.0 - Henrik Ekblad
DESCRIPTION
Motion Sensor example using HC-SR501
http://www.mysensors.org/build/motion
*/
// Enable debug prints
#define MY_DEBUG
// Enable and select radio type attached
#define MY_RADIO_NRF24
//#define MY_RADIO_RFM69
#include <SPI.h>
#include <MySensors.h>
//pir================================================================================================================
unsigned long SLEEP_TIME = 120000; // Sleep time between reports (in milliseconds)
#define DIGITAL_INPUT_SENSOR 2 // The digital input you attached your motion sensor. (Only 2 and 3 generates interrupt!)
#define CHILD_ID 40 // Id of the sensor child
// Initialize motion message
MyMessage msg(CHILD_ID, V_TRIPPED);
bool lasttripped;
//gas================================================================================================================
#define CHILD_ID_MQ 43
/************************Hardware Related Macros************************************/
#define MQ_SENSOR_ANALOG_PIN (4) //define which analog input channel you are going to use
#define RL_VALUE (5) //define the load resistance on the board, in kilo ohms
#define RO_CLEAN_AIR_FACTOR (9.83) //RO_CLEAR_AIR_FACTOR=(Sensor resistance in clean air)/RO,
//which is derived from the chart in datasheet
/***********************Software Related Macros************************************/
#define CALIBARAION_SAMPLE_TIMES (50) //define how many samples you are going to take in the calibration phase
#define CALIBRATION_SAMPLE_INTERVAL (500) //define the time interal(in milisecond) between each samples in the
//cablibration phase
#define READ_SAMPLE_INTERVAL (50) //define how many samples you are going to take in normal operation
#define READ_SAMPLE_TIMES (5) //define the time interal(in milisecond) between each samples in
//normal operation
/**********************Application Related Macros**********************************/
#define GAS_LPG (0)
#define GAS_CO (1)
#define GAS_SMOKE (2)
/*****************************Globals***********************************************/
//VARIABLES
float Ro = 10000.0; // this has to be tuned 10K Ohm
int val = 0; // variable to store the value coming from the sensor
float valMQ = 0.0;
float lastMQ = 0.0;
float LPGCurve[3] = {2.3, 0.21, -0.47}; //two points are taken from the curve.
//with these two points, a line is formed which is "approximately equivalent"
//to the original curve.
//data format:{ x, y, slope}; point1: (lg200, 0.21), point2: (lg10000, -0.59)
float COCurve[3] = {2.3, 0.72, -0.34}; //two points are taken from the curve.
//with these two points, a line is formed which is "approximately equivalent"
//to the original curve.
//data format:{ x, y, slope}; point1: (lg200, 0.72), point2: (lg10000, 0.15)
float SmokeCurve[3] = {2.3, 0.53, -0.44}; //two points are taken from the curve.
//with these two points, a line is formed which is "approximately equivalent"
//to the original curve.
//data format:{ x, y, slope}; point1: (lg200, 0.53), point2:(lg10000,-0.22)
MyMessage msg_gas(CHILD_ID_MQ, V_LEVEL);
unsigned long interval_gas = 10000; // sprawdzanie czasu dla gazu
//light
#define CHILD_ID_LIGHT 44
#define LIGHT_SENSOR_ANALOG_PIN 2
MyMessage msgLight(CHILD_ID_LIGHT, V_LIGHT_LEVEL);
int lastLightLevel;
//dht================================================================================================================
#include <DHT.h>
#define CHILD_ID_HUM 41
#define CHILD_ID_TEMP 42
#define HUMIDITY_SENSOR_DIGITAL_PIN 6
DHT dht;
float lastTemp;
float lastHum;
boolean metric = true;
MyMessage msgHum(CHILD_ID_HUM, V_HUM);
MyMessage msgTemp(CHILD_ID_TEMP, V_TEMP);
unsigned long previousMillis_temp = 0;
const long interval = 10000;
void setup()
{
pinMode(DIGITAL_INPUT_SENSOR, INPUT); // sets the motion sensor digital pin as input
dht.setup(HUMIDITY_SENSOR_DIGITAL_PIN);
metric = getConfig().isMetric;
//gas
Ro = MQCalibration(MQ_SENSOR_ANALOG_PIN); //Calibrating the sensor. Please make sure the sensor is in clean air
}
void presentation() {
//dht
present(CHILD_ID_HUM, S_HUM);
present(CHILD_ID_TEMP, S_TEMP);
//pir
// Send the sketch version information to the gateway and Controller
sendSketchInfo("Piwnica przejscie", "0.3");
// Register all sensors to gw (they will be created as child devices)
present(CHILD_ID, S_MOTION);
attachInterrupt(digitalPinToInterrupt(2), check_pir, CHANGE);
//gas
present(CHILD_ID_MQ, S_AIR_QUALITY);
//light
present(CHILD_ID_LIGHT, S_LIGHT_LEVEL);
}
void loop()
{
unsigned long currentMillis_gas = millis();
unsigned long currentMillis_temp = millis();
if (currentMillis_temp - previousMillis_temp >= interval) {
check_temp();
check_gas();
check_light();
previousMillis_temp = currentMillis_temp;
}
}
void check_light()
{
int lightLevel = (1023 - analogRead(LIGHT_SENSOR_ANALOG_PIN)) / 10.23;
Serial.println(lightLevel);
if (lightLevel != lastLightLevel) {
send(msgLight.set(lightLevel));
lastLightLevel = lightLevel;
}
}
void check_pir()
{
Serial.println("check PIR");
// Read digital motion value
boolean tripped = digitalRead(DIGITAL_INPUT_SENSOR) == HIGH;
Serial.println(tripped);
send(msg.set(tripped ? "1" : "0")); // Send tripped value to gw
}
void check_temp()
{
delay(dht.getMinimumSamplingPeriod());
// Fetch temperatures from DHT sensor
float temperature = dht.getTemperature();
if (isnan(temperature)) {
Serial.println("Failed reading temperature from DHT");
} else if (temperature != lastTemp) {
lastTemp = temperature;
if (!metric) {
temperature = dht.toFahrenheit(temperature);
}
send(msgTemp.set(temperature, 1));
#ifdef MY_DEBUG
Serial.print("T: ");
Serial.println(temperature);
#endif
}
// Fetch humidity from DHT sensor
float humidity = dht.getHumidity();
if (isnan(humidity)) {
Serial.println("Failed reading humidity from DHT");
} else if (humidity != lastHum) {
lastHum = humidity;
send(msgHum.set(humidity, 1));
#ifdef MY_DEBUG
Serial.print("H: ");
Serial.println(humidity);
#endif
}
}
void check_gas()
{
uint16_t valMQ = MQGetGasPercentage(MQRead(MQ_SENSOR_ANALOG_PIN) / Ro, GAS_CO);
Serial.println(val);
Serial.print("LPG:");
Serial.print(MQGetGasPercentage(MQRead(MQ_SENSOR_ANALOG_PIN) / Ro, GAS_LPG) );
Serial.print( "ppm" );
Serial.print(" ");
Serial.print("CO:");
Serial.print(MQGetGasPercentage(MQRead(MQ_SENSOR_ANALOG_PIN) / Ro, GAS_CO) );
Serial.print( "ppm" );
Serial.print(" ");
Serial.print("SMOKE:");
Serial.print(MQGetGasPercentage(MQRead(MQ_SENSOR_ANALOG_PIN) / Ro, GAS_SMOKE) );
Serial.print( "ppm" );
Serial.print("\n");
if (valMQ != lastMQ) {
send(msg_gas.set((int)ceil(valMQ)));
lastMQ = ceil(valMQ);
}
}
float MQResistanceCalculation(int raw_adc)
{
return ( ((float)RL_VALUE * (1023 - raw_adc) / raw_adc));
}
/***************************** MQCalibration ****************************************
Input: mq_pin - analog channel
Output: Ro of the sensor
Remarks: This function assumes that the sensor is in clean air. It use
MQResistanceCalculation to calculates the sensor resistance in clean air
and then divides it with RO_CLEAN_AIR_FACTOR. RO_CLEAN_AIR_FACTOR is about
10, which differs slightly between different sensors.
************************************************************************************/
float MQCalibration(int mq_pin)
{
int i;
float val = 0;
for (i = 0; i < CALIBARAION_SAMPLE_TIMES; i++) { //take multiple samples
val += MQResistanceCalculation(analogRead(mq_pin));
delay(CALIBRATION_SAMPLE_INTERVAL);
}
val = val / CALIBARAION_SAMPLE_TIMES; //calculate the average value
val = val / RO_CLEAN_AIR_FACTOR; //divided by RO_CLEAN_AIR_FACTOR yields the Ro
//according to the chart in the datasheet
return val;
}
/***************************** MQRead *********************************************
Input: mq_pin - analog channel
Output: Rs of the sensor
Remarks: This function use MQResistanceCalculation to caculate the sensor resistenc (Rs).
The Rs changes as the sensor is in the different consentration of the target
gas. The sample times and the time interval between samples could be configured
by changing the definition of the macros.
************************************************************************************/
float MQRead(int mq_pin)
{
int i;
float rs = 0;
for (i = 0; i < READ_SAMPLE_TIMES; i++) {
rs += MQResistanceCalculation(analogRead(mq_pin));
delay(READ_SAMPLE_INTERVAL);
}
rs = rs / READ_SAMPLE_TIMES;
return rs;
}
/***************************** MQGetGasPercentage **********************************
Input: rs_ro_ratio - Rs divided by Ro
gas_id - target gas type
Output: ppm of the target gas
Remarks: This function passes different curves to the MQGetPercentage function which
calculates the ppm (parts per million) of the target gas.
************************************************************************************/
int MQGetGasPercentage(float rs_ro_ratio, int gas_id)
{
if ( gas_id == GAS_LPG ) {
return MQGetPercentage(rs_ro_ratio, LPGCurve);
} else if ( gas_id == GAS_CO ) {
return MQGetPercentage(rs_ro_ratio, COCurve);
} else if ( gas_id == GAS_SMOKE ) {
return MQGetPercentage(rs_ro_ratio, SmokeCurve);
}
return 0;
}
/***************************** MQGetPercentage **********************************
Input: rs_ro_ratio - Rs divided by Ro
pcurve - pointer to the curve of the target gas
Output: ppm of the target gas
Remarks: By using the slope and a point of the line. The x(logarithmic value of ppm)
of the line could be derived if y(rs_ro_ratio) is provided. As it is a
logarithmic coordinate, power of 10 is used to convert the result to non-logarithmic
value.
************************************************************************************/
int MQGetPercentage(float rs_ro_ratio, float *pcurve)
{
return (pow(10, ( ((log(rs_ro_ratio) - pcurve[1]) / pcurve[2]) + pcurve[0])));
}
with 2 sensors