Environment Monitor Using NodeMcu ESP8266

#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BMP085_U.h>
#include <DHT.h>
#define DHTPIN 2 // SO CONNECT THE DHT11/22 SENSOR TO PIN D4 OF THE NODEMCU
#include <ThingSpeak.h>
#include <ESP8266WiFi.h>
#include <ESP8266WiFiMulti.h>
#define SLEEP_DELAY_IN_SECONDS 60*30 // every 30 mins 
/* 
   Connections to BMP180
   ====================
   Connect SCL to  D1
   Connect SDA to  D2
   Connect VDD to 3.3V DC
   Connect GROUND to common ground

    Connections to DH11
   ====================
   Connect Signal pin to D4
   Connect middle pin, usually V+ to 3v3 DC pin on NodeMcu
   Connect - pin to GROUND on NodeMcu

*/
//declare some variables
Adafruit_BMP085_Unified bmp = Adafruit_BMP085_Unified(10085);

char *ssid = "your networks name here";    //  your network SSID (name) 
char *pass = "your network password here";   // your network password
int status = WL_IDLE_STATUS;
WiFiClient  client;
float num = 0;
ESP8266WiFiMulti WiFiMulti;
DHT dht(DHTPIN, DHT11,15);
unsigned long myChannelNumber = your thingspeak channel number; // my thing speak account channel number
const char * myWriteAPIKey = "your thingspeak apikey here";// my thing speak apikey


void setup() {
    Serial.begin(115200); // so we can out put to the screen
    delay(10);

    // We start by connecting to a WiFi network
    WiFiMulti.addAP(ssid, pass);

    Serial.println();
    Serial.println();
    Serial.print("Waiting for WiFi to connect...");

    while(WiFiMulti.run() != WL_CONNECTED) {
    Serial.print(".");
        delay(500);
    }
    // give some feed back that we are connected to router
    Serial.println("");
    Serial.println("WiFi connected");
    Serial.println("IP address: ");
    Serial.println(WiFi.localIP());
    delay(500);

    // connect to thingspeak.com
    if (ThingSpeak.begin(client)) {
    //feed back that we have connected to thingspeak
    Serial.println("connected to ThingSpeak");
    
    dht.begin();
    if(!bmp.begin())
    {
    /* There was a problem detecting the BMP085 ... check your connections */
    Serial.print("Ooops, no BMP180 detected ... Check your wiring or I2C ADDR!");
    while(1);
    }
   
    /* Display some basic information on the BMP180 sensor */
    displaySensorDetails();
    }
    //or we have not!
    else  Serial.println("not connected to ThingSpeak");
    }

// set up complete
 
 
 void loop() {

 
    float pressure = fetchPressure(); /*Get the current pressure from the BMP085 */
    Serial.print("Pressure:    ");
    Serial.print(pressure);
    Serial.println(" mBar");
        
    /* First we get the current temperature from the BMP085 */
    float temperature = fetchTemperature();
    //bmp.getTemperature(&temperature);
    Serial.print("Temperature: ");
    Serial.print(temperature);
    Serial.println(" C");
    
    float humidity = fetchHumidity(); //get humidity from DH11 sensor
    Serial.print("Humidity: ");
    Serial.println(humidity);

    float dewPoint = fetchDewPoint(temperature, humidity);  // calculate dew point fromm temp and humidity data
    Serial.print("Dew Point: ");
    Serial.println(dewPoint);

    // Write to ThingSpeak. There are up to 8 fields in a channel, allowing you to store up to 8 different
    // pieces of information in a channel.  Here, we write to field 1.
    ThingSpeak.setField(1,temperature);
    ThingSpeak.setField(2,pressure);
    ThingSpeak.setField(3,humidity);
    ThingSpeak.setField(4,dewPoint);
    ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);
    WiFi.mode(WIFI_OFF);
    //delay(1000*60*30); // Update ThingSpeak 15 min.
    Serial.println("------------------------------------");
    Serial.print("Entering deep sleep mode for ");
    Serial.print(SLEEP_DELAY_IN_SECONDS);
    Serial.println(" seconds...");
    Serial.println("------------------------------------");
    ESP.deepSleep(SLEEP_DELAY_IN_SECONDS * 1000000, WAKE_RF_DEFAULT);
    //ESP.deepSleep(10 * 1000, WAKE_NO_RFCAL);
  }
  



/**************************************************************************/
void displaySensorDetails(void)
{
  sensor_t sensor;
  bmp.getSensor(&sensor);
  Serial.println("------------------------------------");
  Serial.print  ("Sensor:       "); Serial.println(sensor.name);
  Serial.print  ("Driver Ver:   "); Serial.println(sensor.version);
  Serial.print  ("Unique ID:    "); Serial.println(sensor.sensor_id);
  Serial.print  ("Max Value:    "); Serial.print(sensor.max_value); Serial.println(" mPa");
  Serial.print  ("Min Value:    "); Serial.print(sensor.min_value); Serial.println(" mPa");
  Serial.print  ("Resolution:   "); Serial.print(sensor.resolution); Serial.println(" mPa");  
  Serial.println("------------------------------------");
  Serial.println("");
  delay(500);
}

float fetchHumidity()
{

  float h = dht.readHumidity();
  float t = dht.readTemperature();
    if (isnan(h)) {
    Serial.println("Failed to read from DHT sensor!");
    } else
    {
    return h;
}
}

float fetchPressure()
{
  /* Get a new sensor event */ 
  sensors_event_t event;
  bmp.getEvent(&event);

  if (event.pressure)
  {
    
  float pressure = event.pressure;
 
  
  if (isnan(pressure)) // if its not a number then display error
  {
    Serial.println("Failed to read pressure from BMP180 sensor!");
  }
  else
  return pressure; // return value to calling function
  }
  else
  {
    Serial.println("BMP180 Sensor error");
  }
}


float fetchTemperature()
{
    float temperature;
    bmp.getTemperature(&temperature);
   
    if (isnan(temperature))  // if its not a number then display error
    {
    Serial.println("Failed to read temperature from BMP180 sensor!");
    }
    else
{
    return temperature; // return value to calling function
}
}


float fetchDewPoint(float temperatureC, float humidity)
{

//Calculate dew point

//Specify the constants for water vapor (b) and barometric (c) pressure.
float b = 17.62;
float c = 243.5;
//Calculate the intermediate value 'gamma'
float gamma = log(humidity/100) + b*temperatureC / (c+temperatureC);
//Calculate dew point in Celsius
float dewPoint = c*gamma / (b-gamma);
    if (isnan(dewPoint))  // if its not a number then display error
    {
    Serial.println("Failed to caculate dew point!");
    }
    else
{
    return dewPoint; // return value to calling function
}
}