/* DHT-22 sensor with 12c 16x2 LCD with Arduino uno
   Temperature   and humidity sensor displayed in LCD
   based on: http://www.ardumotive.com/how-to-use-dht-22-sensor-en.html   and
   https://www.ardumotive.com/i2clcden.html for the i2c LCD library by Michalis   Vasilakis
   Recompile by adhitadhitadhit
   Notes: use LCD i2c Library from   link above, i'm not sure why but new Liquidcristal library from Francisco Malpartida   isn't working for me
   other thing, check your */

//Libraries
#include   <dht.h> // sensor library using lib from https://www.ardumotive.com/how-to-use-dht-22-sensor-en.html
#include   <LiquidCrystal_I2C.h> // LCD library using from  https://www.ardumotive.com/i2clcden.html   for the i2c LCD library 
#include <Wire.h> 
#include <ModbusRTUSlave.h>
#include <SoftwareSerial.h>

dht DHT;

//Constants
#define   DHT22_PIN 2     // DHT 22  (AM2302) - pin used for DHT22 
LiquidCrystal_I2C lcd(0x27,16,2);   // set the LCD address to 0x27 after finding it from serial monitor (see comment   above) for a 16 chars and 2 line display
#define SLAVE_ID 1   // Slave ID (1-127)

const byte dePin = 4;
const byte rxPin = 1;
const byte txPin = 0;
SoftwareSerial mySerial(rxPin, txPin);
ModbusRTUSlave modbus(mySerial, dePin); // Use default baud rate
uint16_t holdingRegisters[2];

//Variables
float hum;  //Stores   humidity value
float temp; //Stores temperature value


void setup()
{
     Serial.begin(9600);
    lcd.init();                      // initialize the   lcd 
  // Print a message to the LCD.
  lcd.backlight();
  lcd.setBacklight(HIGH);
    modbus.configureHoldingRegisters(holdingRegisters, 2);  // Configure registers
}

void   loop()
{
    // ModbusRtu.poll();            // Poll for Modbus requests

    int chk = DHT.read22(DHT22_PIN);
    //Read data and store   it to variables hum and temp
    hum = DHT.humidity;
    temp= DHT.temperature;
     //Print temp and humidity values to LCD
    lcd.setCursor(0,0);
    lcd.print("Humidity: ");
    lcd.print(hum);
    lcd.print("%");
    lcd.setCursor(0,1);
     lcd.print("Temp: "); 
    lcd.print(temp);
    lcd.println(" C");
     delay(2000); //Delay 2 sec between temperature/humidity check.
      if (hum > 50){
        digitalWrite(8, HIGH);
        digitalWrite(7, LOW);
        delayMicroseconds(500);
    
    }
       else(hum < 30);
    {
       digitalWrite(8, LOW);
       digitalWrite(7, HIGH);
    }

    // Store values in Modbus registers (correct way)
  holdingRegisters[0] = temp * 10;  // Multiply by 10 for 1 decimal place
  holdingRegisters[1] = hum;
 // uint8_t cbWrite(Modbus::ResultCode event, uint16_t transactionID, void* data) {
  //return 0;

  modbus.poll(); // Check for Modbus requests
  /*
  // Store temperature and humidity values in Modbus registers
  t_reg = DHT.temperature * 10;  // Multiply by 10 for 1 decimal place
  h_reg = DHT.humidity;
  // Function to handle Modbus read requests
uint8_t cbWrite(Modbus::ResultCode event, uint16_t transactionID, void* data) {
  return 0;
}

// Function to handle Modbus write requests (not used in this example)
uint16_t cbRead(Modbus::ResultCode event, uint16_t transactionID, void* data) {
  return 0;
} */
}