/* Modbus RTU common parameters, the Master MUST use the same parameters */
enum {
        MB_SLAVE = 1,	/* modbus slave id */
};
/* slave registers example */
enum {
        MB_REG1,
        MB_REG2,
        MB_REGS	 	/* total number of registers on slave */
};
// Pino onde o Termistor esta conectado
#define PINOTERMISTOR A0
// Valor do termistor na temperatura nominal
#define TERMISTORNOMINAL 10000
// Temp. nominal descrita no Manual
#define TEMPERATURENOMINAL 25
// Número de amostragens para
#define NUMAMOSTRAS 5
// Beta do nosso Termistor
#define BCOEFFICIENT 3950
// valor do resistor em série
#define SERIESRESISTOR 10000
int amostra[NUMAMOSTRAS];
int i;
int valor;
int DS18S20_Pin = A1;
int sensorValue = 0;
OneWire ds(DS18S20_Pin);
int regs[MB_REGS];	/* this is the slave's modbus data map */

void setup()
{
        /* Modbus setup example, the master must use the same COM parameters */
        /* 115200 bps, 8N1, two-device network */
        configure_mb_slave(9600, 'n', 0);
        analogReference(EXTERNAL);
        /*Serial.begin(9600); */
}


void loop() {


        /* This is all for the Modbus slave */
	update_mb_slave(MB_SLAVE, regs, MB_REGS);

	/* your code goes here */
        regs[1] = getTemp();
        regs[2] = valor;
        //analogRead(DS18S20_Pin);




}
 float temperature = getTemp();
        /* Serial.println(temperature); */
float getTemp(){
 //returns the temperature from one DS18S20 in DEG Celsius

 byte data[12];
 byte addr[8];

 if ( !ds.search(addr)) {
   //no more sensors on chain, reset search
   ds.reset_search();
   return -1000;
 }

 if ( OneWire::crc8( addr, 7) != addr[7]) {
   /* Serial.println("CRC is not valid!"); */
   return -1000;
 }

 if ( addr[0] != 0x10 && addr[0] != 0x28) {
   /* Serial.print("Device is not recognized"); */
   return -1000;
 }

 ds.reset();
 ds.select(addr);
 ds.write(0x44,1); // start conversion, with parasite power on at the end

 byte present = ds.reset();
 ds.select(addr);
 ds.write(0xBE); // Read Scratchpad


 for (int i = 0; i < 9; i++) { // we need 9 bytes
  data[i] = ds.read();
 }

 ds.reset_search();

 byte MSB = data[1];
 byte LSB = data[0];

 float tempRead = ((MSB << 8) | LSB); //using two's compliment
 float TemperatureSum = tempRead / 16;

 return TemperatureSum;



   float temperatura;
  float media;

  for (i=0; i< NUMAMOSTRAS; i++) {
   amostra[i] = analogRead(PINOTERMISTOR);
   //delay(10);
  }

  media = 0;
  for (i=0; i< NUMAMOSTRAS; i++) {
     media += amostra[i];
  }
  media /= NUMAMOSTRAS;

  // Converte o valor da tensão em resistência
  media = 1023 / media - 1;
  media = SERIESRESISTOR / media;

  //Faz o cálculo pela fórmula do Fator Beta

  temperatura = media / TERMISTORNOMINAL;     // (R/Ro)
  temperatura = log(temperatura); // ln(R/Ro)
  temperatura /= BCOEFFICIENT;                   // 1/B * ln(R/Ro)
  temperatura += 1.0 / (TEMPERATURENOMINAL + 273.15); // + (1/To)
  temperatura = 1.0 / temperatura;                 // Inverte o valor
  temperatura -= 273.15;
 valor = temperatura;
                              // Converte para Celsius

  /*Serial.print("Temperatura no Sensor eh: ");
  Serial.print(temperatura);
  Serial.println(" *C");

  delay(1000);*/
}