VOLMETRE CODCE

value_VOLTMETRO = analogRead(VOLTMETRO_INPUT);

  vout_VOLTMETRO = (value_VOLTMETRO * 5.11) / 1023.0;
// insert instead of 5.0V the voltage output between the 5V and GND pins of your Arduino


// vin_VOLTMETRO = vout_VOLTMETRO x CALIBRATION VALUE; THE CALIBRATION VALUE
// is GIVEN BY TOTAL VOLTAGE / VOLTAGE ON THE 2nd RESISTANCE, OR (V ON THE TOTAL RESISTANCE R1 + R2) / V ON THE R2
// in this case V TOT is 12.42V, while V on R2 is 0.64V so the CALIBRATION VAL is 12.42 / 0.64 = 19.40

  vin_VOLTMETRO = vout_VOLTMETRO * 10.8947;


  if (vin_VOLTMETRO < 0.09) {
    vin_VOLTMETRO = 0.0;
  }

  NxSerial.write("t25.txt=");// puts calculated Voltage (float) in text-field t3.txt
  NxSerial.write(0x22);
  NxSerial.print(vin_VOLTMETRO, 2); // valore a 2 cifre decimali
  NxSerial.write(0x22);
  NxSerial.write(0xff);
  NxSerial.write(0xff);
  NxSerial.write(0xff);


  Serial.println("-------------------------------");
  Serial.println("");
  Serial.print("VOLTMETRO: ");
  Serial.print(vin_VOLTMETRO, 2);
  Serial.println(" V");

}