SelfWateringPlanter.ino

// Includes temperature sensor library (DHT11) //
#include "dht.h"
// Includes library needed for the I2C backpack of LCD and other LCD
libraries\
#include "Wire.h"
#include "LCD.h"
#include "LiquidCrystal_I2C.h"
// Defines the pins used by the temperature sensor\
#define DHTTYPE DHT11
#define DHTPIN 6\
DHT dht(DHTPIN, DHTTYPE);
//Set the pins on the I2C chip used for LCD connections
//ADDR,EN,R/W,RS,D4,D5,D6,D7
LiquidCrystal_I2C lcd(0x3F,2,1,0,4,5,6,7);
// pH sensor //
#include <SoftwareSerial.h>
//we have to include the SoftwareSerial library, or else we can't use it #define rx 8
 //define what pin rx is going to be
#define tx 9
 //define what pin tx is going to be
SoftwareSerial myserial(rx, tx);
//define how the soft serial port is going to work
String inputstring = "";
//a string to hold incoming data from the PC
String sensorstring = "";
//a string to hold the data from the Atlas Scientific product boolean input_string_complete = false;
//have we received all the data from the PC
boolean sensor_string_complete = false;
//have we received all the data from the Atlas Scientific product
// These two variables will be used to hold the value generated by the pH sensor
float pH;
float ultimatepH = 0;
// Defines the pin numbers for the sensors in the arduino
const int conductivityPin = A0;
const int waterSensorPin = A1;
const int pumpOnePin = 11;
const int pumpTwoPin = 10;
boolean phIsOff = true;
boolean lowWater = false;
const float desiredPh = 4.5;
int counter = 0;
int frontScreen = 1;

void setup(){
  //Debugging
Serial.begin(9600); // Air pump //
  pinMode(7, OUTPUT);
  // Pump One //
  pinMode(pumpOnePin, OUTPUT);
  // Pump Two //
  pinMode(pumpTwoPin, OUTPUT);
  // Button //
  pinMode(13, INPUT);
  AirPumpOn();
  // initializes pH sensor //
  myserial.begin(9600);
 //set baud rate for the software serial port to 9600
  inputstring.reserve(10);
//set aside some bytes for receiving data from the PC
  sensorstring.reserve(30);
//set aside some bytes for receiving data from Atlas Scientific product
   // initializes LCD module
   lcd.begin (16,2); // 16 x 2 LCD module
   lcd.setBacklightPin(3,POSITIVE); // BL, BL_POL
   lcd.setBacklight(HIGH);
  //digitalWrite(2, HIGH);
  //turnPumpTwo(true);
}
void loop() {
  ultimatepH = digitalRead(13);
  // Get pH level
  if (input_string_complete) { //if a string from the PC has been received in its entirety
    myserial.print(inputstring);
//send that string to the Atlas Scientific product
    myserial.print('\\r');
//add a <CR> to the end of the string
    inputstring = "";
//clear the string
    input_string_complete = false;
 //reset the flag used to tell if we have received a completed string from the PC
}
  if (myserial.available() > 0) {
//if we see that the Atlas Scientific product has sent a character
    char inchar = (char)myserial.read();


//get the char we just received
    sensorstring += inchar;
//add the char to the var called sensorstring
    if (inchar == '\\r') {
//if the incoming character is a <CR>\
      sensor_string_complete = true;
 //set the flag
} }
  if (sensor_string_complete == true) {
//if a string from the Atlas Scientific product has been received in its entirety
    pH = sensorstring.toFloat();
//send that string to the PC's serial monitor
    sensorstring = "";
//clear the string
    sensor_string_complete = false;
 //reset the flag used to tell if we have received a completed string from the Atlas Scientific product
} Serial.println(pH);
  // Checks if the pH sensor has started to record a value
  if(pH != 0) {
    phIsOff = false;
  }
  // If not, then it won't start the loop
  if(!pH) {
return; }
  // If the water is too low, it will load water
  if(loadWaterByLevel()) {
    delay(500);
    return;
}
  // If the pH level is above/below threshold, it will replace the water in the tank
  if(!checkPh()) {
    if(counter == 6) {
counter = 0;
      frontScreen = -frontScreen;
    }
// Debug value Serial.println(frontScreen);
    // This if/else block will alternate what is displayed on the
    // LCD screen. In the first state, it will display the temperature,
    // and the humidity. In the second state, it will display the pH value
    // and the H2O EC.
    if(frontScreen == 1) {
      lcd.clear();\
      lcd.print("- Temp: ");


      lcd.print(GetTemperature());
      lcd.print("C");
      lcd.setCursor(0,1);
      lcd.print("- Humidity: ");
      lcd.print(GetHumidity());
      lcd.print("%");\
    } else {
      lcd.clear();
      lcd.print("- pH level: ");
      lcd.print(pH);
      lcd.setCursor(0,1);
      lcd.print("- H2O EC: ");
      lcd.print(GetConductivityValue());
    }
    counter++;
    delay(500);
} }
// Checks if the pH level is above or below the threshold\
bool checkPh() {
  if(ultimatepH == 1) {
    turnPumpOne(true);
    AirPumpOff();
    lcd.clear();
    lcd.print("- low pH lvl");
    lcd.setCursor(0,1);
    lcd.print("Removing H2O");
    delay(30000);
    AirPumpOn();
  }
}
// Loads water into the tank if the level is too low
bool loadWaterByLevel() {
  if(GetWaterLevel() <= 480) {
    turnPumpTwo(true);
    turnPumpOne(false);
    lcd.clear();
    lcd.print("- low water lvl");
    lcd.setCursor(0,1);
    lcd.print("- Adding water");
    return true;
  } else {
    turnPumpOne(false);
    turnPumpTwo(false);
    return false;
} }
// Gets conductivity value
int GetConductivityValue() {
  return analogRead(conductivityPin);
}
// Gets water sensor level

int GetWaterLevel() {
  return analogRead(waterSensorPin);
}
// Turns air pump on
void AirPumpOn() {
  digitalWrite(7, HIGH);
}
// Turns air pump off
void AirPumpOff() {
  digitalWrite(7, LOW);
}
// Gets the humidity from the DHT11 sensor
float GetHumidity() {
  return dht.readHumidity();
}
// Gets the temperature from the DHT11 sensor
float GetTemperature() {
  return dht.readTemperature();
}
// Turns pump one on or off //
void turnPumpOne(boolean state) {
  if(state) {
    digitalWrite(pumpOnePin, HIGH);
  } else {
    digitalWrite(pumpOnePin, LOW);
  }
}
// Turns pump two on or off //
void turnPumpTwo(boolean state) {
  if(state) {
    digitalWrite(pumpTwoPin, HIGH);
  } else {
    digitalWrite(pumpTwoPin, LOW);
  }
}