Aplicación del sistema de archivos FatFS en MCU

				
					/* USB HOST MSC operation function, this part of the function is set according to needs */
static void MSC_Application(void)
{
  FRESULT res; /* FatFs function return value */
  uint32_t byteswritten, bytesread; /* Number of files read and written */
  uint8_t wtext[] = "This is STM32 working with FatFs!"; /* Write file buffer */
uint8_t wtext2[] = "This is an example of FatFs reading and writing!"; /* Write file buffer */
uint8_t wtext3[] = "This is a test of appending data to a file!"; /* Write file buffer */
  uint8_t rtext[100]; /* Read file buffer */
 
  /* Register the file system object to the FatFs module */
  if(f_mount(&USBHFatFS, (TCHAR const*)USBHPath, 0) != FR_OK)
{
    /* Error handling */
    Error_Handler();
}
  else
{
    /* Open a file */
    if(f_open(&USBHFile, "STM32.TXT", FA_OPEN_EXISTING | FA_WRITE) != FR_OK)
   {
      /* Error handling */
      Error_Handler();
   }
    else
   {
      res=f_lseek(&USBHFile,f_size(&USBHFile)); //Point the pointer to the end of the file
      //res=f_lseek(&USBHFile,100); //Point the pointer to the end of the file
      /* Write data to file */
      res = f_write(&USBHFile, wtext, sizeof(wtext), (void *)&byteswritten);
      res = f_write(&USBHFile, "\r\n", sizeof("\r\n")-1, &byteswritten);
      res = f_write(&USBHFile, wtext2, sizeof(wtext2), (void *)&byteswritten);
      res = f_write(&USBHFile, "\r\n", sizeof("\r\n")-1, &byteswritten);
      res = f_write(&USBHFile, wtext3, sizeof(wtext3), (void *)&byteswritten);
      res = f_write(&USBHFile, "\r\n", sizeof("\r\n")-1, &byteswritten);
     
      if((byteswritten == 0) || (res != FR_OK))
     {
        /* Error handling */
        Error_Handler();
     }
      else
     {
        /* Close file */
        f_close(&USBHFile);
       
        /* Open file for reading */
        if(f_open(&USBHFile, "STM32.TXT", FA_READ) != FR_OK)
       {
          /* Error handling */
          Error_Handler();
       }
        else
       {
          /* Read data from file */
          res = f_read(&USBHFile, rtext, sizeof(rtext), (void *)&bytesread);
         
          if((bytesread == 0) || (res != FR_OK))
         {
            /* Error handling */
            Error_Handler();
         }
          else
         {
            /* Close file */
            f_close(&USBHFile);
           
            /* Compare read and written data */
            if((bytesread != byteswritten))
           {
              /* Error handling */
              Error_Handler();
           }
            else
           {
              /* No errors */
             
           }
         }
       }
     }
   }
}
 
  FATFS_UnLinkDriver(USBHPath);
}