MEGR 3171 DIY Weather Dashboard

//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//INCLUDE NECESSARY LIBRARIES AND INITIALIZE VARIABLES
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

#include <LiquidCrystal.h> //include library for a 16x2 LCD display

//int ledPin = D7;// can be used to check if they communicate, not implemented in this version

//init. values to be displayed on LCD
int temp, hum, pres, rain;

//initialize current value, this var tracks which value should be displayed, as the values will loop
int currentValue = 0;

// Variable to keep track of the time elapsed between each display, ini at 0
unsigned long previousMillis = 0;

// Interval between each display in milliseconds, equivalent to 20sec
const unsigned long interval = 20000;
//init. digital pins for lcd display
LiquidCrystal lcd(5, 4, 3, 2, 1, 0);

//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//SETUP FUNCTION INITIALIZES LCD DISPLAY AND SUBSCRIBES TO PARTICLE EVENTS
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
void setup() {
    //pinMode(ledPin, OUTPUT); //not used in this version, can be used to check communication between argons
    lcd.clear(); // clear screen
    lcd.begin(16, 2);//initialize lcd
    lcd.setCursor(0, 0);//set at beginning of line 1
    lcd.print("DIY Weather Dash");
    lcd.setCursor(0,1);//set cursor to beginning of line 2
    lcd.print("Stay Tuned...");//placeholder message while argons initiate and is waiting for published data
    //subscribe to data published from other argon
    Particle.subscribe("Temp (C):", displayTempData);
    Particle.subscribe("Pressure (hPa):", displayPresData);
    Particle.subscribe("Humidity (%):", displayHumData);
    Particle.subscribe("Raining:", displayRainData);
}

//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//CONSTANT LOOP CONTROLS THE LCD DISPLAY CYCLE
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
void loop() {
    // Check if it's time to display the next value
    unsigned long currentMillis = millis(); // set currentmillis to system clock time
    //current millis will keep incrementing, but when the diff between current and previous is more than 20000, activate if statement
    if (currentMillis - previousMillis >= interval) {
        //set previousMillis to currentMillis, this means that on next loop iteration difference will begin at 0 again, again begin increasing back to 20k
        previousMillis = currentMillis;
    
        // Set cursor to 2nd line on the LCD screen
        lcd.setCursor(0, 1);
    
        // Update the current value being displayed (temp,pres,hum,or rain)
        currentValue = (currentValue + 1) % 4; // the % is a remainder operator, which ensures that the value never increments past 3
  }
    //Particle.publish("all_clear",)
}

//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//FUNCTIONS TO HANDLE THE DISPLAY BASED ON WHICH EVENT VALUE SHOULD BE DISPLAYED
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

//function that handles displaying Temperature value
void displayTempData(const char* eventName, const char*data){
    //convert the published char value to an integer
    temp = atoi(data);
    //check if this value should be displayed based on main loop fxn
    if (currentValue == 0) {
        lcd.setCursor(0, 1);//set cursor to 2nd line
        lcd.print("                ");//clear line by printing 16 blank space chars
        lcd.setCursor(0, 1);//place cursor back to beginning of 2nd line
        //display temp in Celsius
        lcd.print("Temp: ");
        lcd.print(temp);
        lcd.print(" C");
    }
}

//function that handles displaying Pressure value
void displayPresData(const char* eventName, const char*data){
    //convert the published char value to an integer
    pres = atoi(data);
    //check if this value should be displayed based on main loop fxn
    if (currentValue == 1) {
        lcd.setCursor(0, 1);//cursor @ 2nd line
        lcd.print("                ");//clear previous
        lcd.setCursor(0, 1);//cursor @ start of 2nd line
        //display Pressure in hPa
        lcd.print("Pres: ");
        lcd.print(pres);
        lcd.print(" hPa");
    }
}

//fxn that handles displaying humidity values
void displayHumData(const char* eventName, const char*data){
    //convert the published char value to an integer
    hum = atoi(data);
    //check if this value should be displayed based on main loop fxn
    if (currentValue == 2) {
        lcd.setCursor(0, 1);//cursor @ 2nd line
        lcd.print("                "); // clear line
        lcd.setCursor(0, 1);//cursor back to beginning of 2nd line
        //display humidity as percentage
        lcd.print("Humidity: ");
        lcd.print(hum);
        lcd.print("%");
    }
}

//fxn that handles displaying rain status
void displayRainData(const char* eventName, const char*data){
    //convert the published char value to an integer
    rain = atoi(data);
    //check if this value should be displayed based on main loop fxn
    if (currentValue == 3) {
        
        //check whether to display that it is or isnt raining, this is based on a threshold, as when not wet, DGZZI reads between 0 and 20 generally
        if (rain >= 100){ // if it is above 100, it is typically actively raining, and not simply leftover water droplets from an already passed storm, or from dew
            lcd.setCursor(0, 1);//cursor @ 2nd line
            lcd.print("                "); // clear line
            lcd.setCursor(0, 1);//cursor back to beginning of 2nd line
            //display rain status as yes or no
            lcd.print("It is raining!");
        }
        else{
            lcd.setCursor(0, 1);//cursor @ 2nd line
            lcd.print("                "); // clear line
            lcd.setCursor(0, 1);//cursor back to beginning of 2nd line
            //display rain status as yes or no
            lcd.print("Not raining.");
        }
    }
}
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