Save data with atmega 328

Projects General Guidance
7

Here is the code I used to prove out the SD function in my project. I suggest you do the same. Meaning get the SD working then add in the sensors.

/*
  SD card read/write
  Mod 01 make file name a string and iterate until we find a unused file name.
  Mod 02 add capability to increment filename.
  Rev 03 tested successfully on Arduino M0

  SD card attached to SPI bus on ICSP Header.
  SD Board power = 5V (for large board with EEPROM)

  based on code created: Nov 2010 by David A. Mellis, 9 Apr 2012 by Tom Igoe
  This code is in the public domain.

driver has a 512 byte buffer then write to SD

Closing the file forces any buffered data to be written to the SD and also updates
the file's directory entry.

If you don't close the file, you will lose all data written the file since it was opened,
not just the last buffer, since the directory entry will not be updated.
*/

#include <SPI.h>
#include <SD.h>

// *** SD Card declarations **************************************************
// ***************************************************************************

#define SDCARD_CS_PIN 4

uint8_t fileNumb = 100;
char dataFile[8];
bool SD_Error = false;

File myFile;			// create instance of a "File" class

void setup() {
  SerialUSB.begin(115200);
  delay (2000);
// Initializing SD card....
  if (!SD.begin(SDCARD_CS_PIN))
    {SerialUSB.print("initialization failed");
     SD_Error = true;
    }

// loop until we find a file that doesn't already exist.......
  do
    {
     itoa(fileNumb, dataFile, 10);  // (value, Array, base)
     const char *extension = ".csv";
     strcat(dataFile, extension);  // syntax  strcat(dest, source)
     ++fileNumb;
    } while (SD.exists(dataFile));


SerialUSB.print("READY TO OPEN FILE FOR WRITING   = ");
SerialUSB.println(dataFile);
  myFile = SD.open(dataFile, FILE_WRITE);   // <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
SerialUSB.println(myFile);
  // if the file opened okay, write to it:
  if (myFile) {
    myFile.println("data from boiler");     // <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
    SerialUSB.println("data from boiler");
    //SerialUSB.print(" data written to file:   ");
    myFile.close();                         // <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
 SerialUSB.println(dataFile);
    }
  else {
    // if the file didn't open, print an error:
    SD_Error = true;
    }
  SerialUSB.print("SD_Error = ");
  SerialUSB.print(SD_Error);
}
void loop() {
  // nothing happens after setup
}