RTX RAM Drive Problem with MCBSTM32E

Hi, every one, I'm trying to use RAM drive with RL-Flash File System on blinky example.

I use MCBSTM32E board , I follow up RL-Flash File System guide instructions.

import FS_CM3.lib, copy retarget and file File_config.c to project library.

I configured File_config.c like this,

Number of open Files :8
CPU Clock Fq :60000000

device size : 0x0000 4000
number of Sector : 32
relocate device buffer : Yes
Default Drive : Yes

I modifed File_ex1 capture_file fonc. and clean all blinky tasks. Just work Task2 . I add serial output end of code too.

/*----------------------------------------------------------------------------
 *        Task 2 'phaseB': Phase B output
 *---------------------------------------------------------------------------*/
__task void phaseB (void) {
  for (;;) {

   LED_On(LED_A);
   os_dly_wait (50);
   LED_Off(LED_A);
   os_dly_wait (50);

   os_dly_wait(250);
   printf("Check Serial\n\r");
   capture_file('a');

  }
}


/*----------------------------------------------------------------------------
 * Capture / Create File
 *---------------------------------------------------------------------------*/

void capture_file (char mode) {
  FILE *f;
  char *fmode;

  if (mode == 'C') {                  /* Capture file                        */
    printf("\nCapture data to file: %s",filename);
    fmode = "w";
  }
  else {                              /* Append file                         */
    printf("\nAppend data to file: %s",filename);
    fmode = "a";
  }
  printf("\nPress ESC to stop.\n");

  f = fopen (filename,fmode);         /* open a file for writing             */
  if (f == NULL) {
    printf ("\nCan not open file!\n");/* error when trying to open file      */
    return;
  }
  fprintf (f, "SAMPLE TEXT\n\r");


  fclose (f);                         /* close the output file               */
  printf ("\nFile closed.\n");
}

Serial Out put like this,

[RX] - Check Serial<CR><LF>
<CR>
<CR><LF>
Append data to file: R:\Dump_file.log<CR><LF>
Press ESC to stop.<CR><LF>
<CR><LF>
Can not open file!<CR><LF>
Check Serial<CR><LF>
<CR>
<CR><LF>
Append data to file: R:\Dump_file.log<CR><LF>
Press ESC to stop.<CR><LF>
<CR><LF>
Can not open file!<CR><LF>

I used SD card before with same board, it was sample GPS logger. I logged GPRMC data to SD file. I remembered just importing SDIO_STM32F103.c.I rememeber can easly crate and write files on SD.

I just need 16Kb data storage on RAM drive for buffer. It has to be easy as SD card example.

Did I missed some configration file, Thanks your help guidence

Best Regards.