Logging.ino

#ifdef USE_LOGGING
  boolean SD_OK;
  
  void SetupSD()
  {
      // make sure that the default chip select pin of SDI is set to
      // output, even if you don't use it:
      pinMode(10, OUTPUT);
      // see if the card is present and can be initialized:
      if (!SD.begin(4)) 
      {
          SD_OK = false;
      }
      SdFile::dateTimeCallback(dateTime); // set callback for SD file date
      SD_OK = true;
  }
  
  void OpenLogFile()
  {
      if(SD_OK)
      {
          char fileName[20];
          int fileCounter = 0;
          // scan card until file not found
          do
          {
              fileCounter++;
              sprintf(fileName,"%02d%02d_%03d.csv",month(),day(),fileCounter);
          } 
          while (SD.exists(fileName) && fileCounter<100);
          // now create the new filename
          logFile = SD.open(fileName, O_CREAT | O_WRITE); // do not use FILE_WRITE. It is 100x slower
          WriteDateToLog();
      }
  }
  
  void CloseLogFile()
  {
      if(SD_OK)
      {
          logFile.close();
      }
  }
  
  void WriteDateToLog()
  {
      if(SD_OK)
      {
          logFile << year() << "-" << month() << "-" << day() << ";";
          logFile << hour() << ":" << minute() << ":" << second() << ";";
          logFile.flush();
      }
  }
     
  // this function is called by SD if it wants to know the time
  void dateTime(uint16_t* date, uint16_t* time) 
  {
      // return date using FAT_DATE macro to format fields
      *date = FAT_DATE(year(), month(), day());
      // return time using FAT_TIME macro to format fields
      *time = FAT_TIME(hour(), minute(), second());
  }   
#endif