myWeather2.ino

/*********************************************************************
This is an example of a solution which employs Arduino along with the 
DHT11 Temperature and Humidy sensor and SSD1306 display

This example is for a 128x64 size display using I2C to communicate
3 pins are required to interface (2 I2C and one reset)


Written by Johnathan Lightfoot
BSD license, check license.txt for more information
All text above, and the splash screen must be included in any redistribution
*********************************************************************/

#include <Wire.h>
// two libraries inserted into the 'libraries' folder
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
// dht library
#include "DHT.h"

#define DHTPIN 2     // what digital pin we're connected to
#define OLED_RESET 4 
Adafruit_SSD1306 display(OLED_RESET); //Resets the OLED

//#define DHTTYPE DHT22
#define DHTTYPE    DHT11     // DHT 11 

//Checks if the display is of the correct size
#if (SSD1306_LCDHEIGHT != 64)
#error("Height incorrect, please fix Adafruit_SSD1306.h!");
#endif

//Declares DHT pin and type
DHT dht(DHTPIN, DHTTYPE);

//Set hot and cold limits
const int hot = 82.0; //set hot parameter
const int cold = 75.0; //set cold parameter

void setup()   {                
//Define pin inputs and outputs  
  pinMode(A2, INPUT); //sensor
  pinMode(3, OUTPUT); //blue
  pinMode(4, OUTPUT); //green
  pinMode(5, OUTPUT); //red
  //Begin Serial port for displaying on data in the Serial Monitor
  Serial.begin(9600);
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);  // initialize with the I2C addr 0x3D (for the 128x64)
  display.display(); // show splashscreen
  delay(2000); 
  display.clearDisplay();   // clears the screen and buffer
  
  dht.begin();
  delay(2000);
}

void loop() {
  //int sensor = analogRead(A2);
  //float voltage = (sensor / 1024.0) * 5.0;
  //float tempC = (voltage - .5) * 100;
  //float tempF = (tempC * 1.8) + 32;
  //Serial.print(F("temp: "));
  //Serial.print(tempF);
    display.clearDisplay();
    display.setTextSize(2);
    display.setTextColor(WHITE);
    display.setCursor(0,0);
    //display.println(F("Inside Tmp"));
   
  float h = dht.readHumidity();
  // Read temperature as Celsius (isCelsius = true)
  float t = dht.readTemperature(true);
  // Read temperature as Fahrenheit (the default)
  float f = dht.readTemperature();

  // Check if any reads failed.
  if (isnan(h) || isnan(t) || isnan(f)) {
    delay(2000);
  } else{
    // routine for converting temp/hum floats to char arrays
    char temp_buff[5]; char hum_buff[5];
    char temp_disp_buff[11] = "Temp:";
    char hum_disp_buff[11] = "Hum:";
    
    // appending temp/hum to buffers
    dtostrf(t,2,1,temp_buff);
    strcat(temp_disp_buff,temp_buff);
    dtostrf(h,2,1,hum_buff);
    strcat(hum_disp_buff,hum_buff);

    if (dht.readTemperature(true) < cold) { //cold
    digitalWrite(3, LOW);
    digitalWrite(4, LOW);
    digitalWrite(5, HIGH);
    display.println(F("Too Cold"));
    //Serial.println(F(" Too Cold."));
    Serial.println(dht.readTemperature(true));
  }
  else if (dht.readTemperature(true) >= hot) { //hot
    digitalWrite(3, HIGH);
    digitalWrite(4, LOW);
    digitalWrite(5, LOW);
    display.println(F("Too Hot"));
    //Serial.println(F(" Too Hot."));
    Serial.println(f = dht.readTemperature(true));
  }
  else { //fine
    digitalWrite(3, LOW);
    digitalWrite(4, HIGH);
    digitalWrite(5, LOW);
    display.println(F("Ideal"));
    //Serial.println(F(" It's Fine."));
    Serial.println(f = dht.readTemperature(true));
  }
    
    // routine for displaying text for temp/hum readout
    display.setCursor(0,17);
    display.println(temp_disp_buff);
    display.println(hum_disp_buff);
    display.display();
    delay(2000);
  }
}