Arduino Power Monitor v1.2

/*
 * Arduino Power Monitor v1.2
 *
 * learnelectronics
 * 18 JUL 2017, 25 JULY 2017
 *
 * www.youtube.com/c/learnelectronics
 * [email protected]
 */

#include <Wire.h>                                             //wire library for I2C comms
#include <INA219.h>                                           //driver for the ina219
#include <DS3231.h>
#include <SPI.h>                                              //Serial library for SD card shield
#include <SD.h>





INA219 monitor;                                               //create instance of the INA219 called monitor

DS3231 Clock;

const int chipSelect = 4;


byte year, month, date, DoW, hour, minute, second;




void setup()   {

  Serial.begin(9600);
  Wire.begin();
  monitor.begin();                                            //start the ina219

   Serial.print("Initializing SD card...");


  if (!SD.begin(chipSelect)) {
    Serial.println("Card failed, or not present");
    // don't do anything more:
    return;
  }
  Serial.println("card initialized.");

}


void loop() {


  Clock.getTime(year, month, date, DoW, hour, minute, second);

  Serial.print("shunt V: ");                                 //send title to serial monitor
  Serial.print(monitor.shuntVoltage() * 1000, 2);            //send shunt voltage to serial monitor in mV with 2 dec places
  Serial.println(" mV");                                     //send units to serial monitor

  Serial.print("shunt I: ");
  Serial.print(monitor.shuntCurrent() * 1000, 2);
  Serial.println(" mA");

  Serial.print("bus V:   ");
  Serial.print(monitor.busVoltage(), 2);
  Serial.println(" V");

  Serial.print("bus P:   ");
  Serial.print(monitor.busPower() * 1000, 2);
  Serial.println(" mW");

  Serial.println("");
  Serial.print(hour, DEC);
  Serial.print(":");
  Serial.print(minute, DEC);
  Serial.print(":");
  Serial.print(second, DEC);
  Serial.print(" ");
  Serial.print(date, DEC);
  Serial.print("/");
  Serial.print(month, DEC);
  Serial.print("/");
  Serial.println(year, DEC);





 String dataString = "";                                  //create an empty string var called dataString
 float shuntVolt = (monitor.shuntVoltage() * 1000);       //hold value of monitor.shuntVoltage() in float var called shuntVolt
 float shuntCurr = (monitor.shuntCurrent() * 1000);       //hold value of monitor.shuntCurent() in float var called shuntCurr
 float busVolt = (monitor.busVoltage());                  //hold value of monitor.busVoltage() in float var called busVolt
 float busPow = (monitor.busPower() * 1000);              //hold value of monitor.busPower() in float var called busPow

 dataString += String(date);                              //add the var date, cast as a string to the current dataString var
 dataString += ",";                                       //add a comma to the current dataString
 dataString += String(month);                             //and so on
 dataString += ",";                                       //and so forth
 dataString += String(year);
 dataString += ",";
 dataString += String(hour);
 dataString += ",";
 dataString += String(minute);
 dataString += ",";
 dataString += String(second);
 dataString += ",";
 dataString += String(shuntVolt);
 dataString += ",";
 dataString += String(shuntCurr);
 dataString += ",";
 dataString += String(busVolt);
 dataString += ",";
 dataString += String(busPow);

  File dataFile = SD.open("datalog.txt", FILE_WRITE);       // if the file is available, write to it:


  if (dataFile) {
    dataFile.println(dataString);
    dataFile.close();

    Serial.println(dataString);                             // print to the serial port too:
  }

  else {                                                    // if the file isn't open, pop up an error:
    Serial.println("error opening datalog.txt");


}
 delay(5000);                                               //wait some amount of time between logging (you can set your own)
}