// The University of Arizona
// College of Engineering * 2021 Summer Engineering Academy *
// Biosystems Engineering Department
// Vegetation Index and Phenology Lab (vip.arizona.edu)
// Dr. Kamel Didan
// Dr. Armando Barreto Munoz
// Mr. Truman P. Combs
// Ms. Madeline Melichar
// Learn about our lab at this site vip.arizona.edu
/* 
  We work in the following fields 
* We work with NASA on their Earth Observing Satellites
* We develop Image processing tools and science algorithms 
* We teach Engineers about UAS &  Drones and Proximal sensing to monitor and observe the Environment
* We work with Big Geospatial data, the science required to work with it, and implement Machine Learning tools for smart solution to environemental monitoring 
* And More.....
*/ 


/* About this Project
========================

  This Arduino program will communicate with a temperature and humidity sensor (DHT22 or AHT10) 
  It wil then collect data and displays it to the serial monitor or serial plotter 
  If you wish you can capture this data & analyze and/or plot it
*/

// Libraries to work with the Temp and Humidity sensors 
#include <dht.h>              // Library for DHT22

// Define the pins to where the LEDS will be attached 

#define LED_Humidity_Pin  3 // D3 PIN -  This LED will glow if Humidity exceeds a certain number
#define LED_Temp_Pin      4 // D3 PIN - This LED will glow if Temperature exceeds a certain number


// Define the pin to which the DHT22 sensor will be attched
#define DHT22_Pin 2         // D2 PIN

dht DHT;                    // Create a DHT object to work with the sensors and library

// Declare Global variables for Temp and Humidity to hold the data read by the sensor
float DHT22_Humidity,DHT22_Temp;

void setup() {
// Initialize the communication protocol 
  Serial.begin(9600);  // Use a 9600 Baud Rate - basically a speed of communication

// Set the LED output for humidity and Temp
  pinMode(LED_Humidity_Pin, OUTPUT); // Set the LED as an output mode so we can send a pulse to it when needed
  pinMode(LED_Temp_Pin, OUTPUT);    // Set the LED as an output mode so we can send a pulse to it when needed

// Create label for the plot if needed
  Serial.flush();
  Serial.println("DHT22_Temp , DHT22_Humidity");
}
 
void loop() {

// Call a function that reads the data form the DHT22 sensor
  Get_DHT22_Data();

  // Print the data in order so it could be labelled & plotted 
  Serial.print(DHT22_Temp);Serial.print(","); Serial.print(DHT22_Humidity);
  Serial.println();

// Test the Status of Humidity and Temperature and turn ON/OFF the corresponding LED
  if (DHT22_Humidity > 30){
    digitalWrite(LED_Humidity_Pin, HIGH);    // Turn the LED on (HIGH is the voltage level)
    delay(250);                             // Wait for a quarter of a second
    digitalWrite(LED_Humidity_Pin, LOW);     // Turn the LED off by making the voltage LOW
    delay(250);                             // Wait for a quarter of a second
  }
  if (DHT22_Temp > 30.0){
    digitalWrite(LED_Temp_Pin, HIGH);
    delay(250);                      
    digitalWrite(LED_Temp_Pin, LOW); 
    delay(250);    
  }
}

void Get_DHT22_Data(){
  // Read the Sensor data 
  int readData = DHT.read22(DHT22_Pin); // Reads the data from the sensor
  
  DHT22_Temp = DHT.temperature; // Gets the values of the temperature
  DHT22_Humidity = DHT.humidity; // Gets the values of the humidity
}