Compiler/TMS320F28377S: Use of FatFs with TMS320F28377S--probleum with "f_open"

Tool/software: TI C/C++ Compiler

Hello ,

I am using example code "usb_host_msc"  and it is working fine but I want to create file in USB. for this I write following code just before while(1) so first file created and when "ls" command run then it show file, but this is not working what is wrong ??

Here I set flag "t" (global variable). f_open return "FR_OK", "FR_NOT_READY" then this flag set accordingly. This is always set to 2 mean  "FR_NOT_READY".  

FIL fil; /* File object */
FRESULT fr; /* FatFs return code */

f_mount(0, &g_sFatFs);

//open_file();

fr = f_open(&fil,"age.txt", FA_CREATE_ALWAYS);

if(fr==FR_OK){
t=1;
}
else if(fr==FR_NOT_READY){
t=2;
}
else if(fr== FR_NO_FILE){
t=3;
}
else if(fr== FR_NO_PATH){
t=4;
}
else if(fr==FR_INVALID_NAME){
t=5;
}
else if(fr==FR_INVALID_DRIVE){
t=6;
}
else if(fr==FR_DENIED){
t=7;
}
else {
t=100;
}

f_close(&fil);

while(1)
{