#include <Wire.h>

const int DS1115_Address = 0x48;  // I2C address of DS1115
float voltageValue = 0.0;

void setup() {
  Serial.begin(9600);
  Wire.begin();
}

void loop() {
  int rawValue;
  Wire.beginTransmission(DS1115_Address);
  Wire.write(0x00); // address of conversion register
  Wire.endTransmission();
  delay(10);  // conversion time for DS1115
  Wire.requestFrom(DS1115_Address, 2);
  if (Wire.available() == 2) {
    rawValue = Wire.read() << 8 | Wire.read();
    voltageValue = rawValue * 5.0 / 32768.0; // 5V reference voltage, 16-bit resolution
    Serial.print("Voltage: ");
    Serial.print(voltageValue);
    Serial.println("V");
  }
  delay(1000);
}