Question regarding an issue, L138/C6748 with BLED112 usb dongle

Hi-

I'm using LCDK board and trying to use BLED112 bluetooth usb dongle via USB OTG port.

Unfortunately, C6748_StarterWare_1.20.04.01 doesn't have USBCDC host example.

My first question is
Is there a reason why it doesn't have USBCDC host example? Is LCDK able to support usb host cdc?

I found an usb host cdc example from link below, but I was not able to read or write the usb dongle.
github.com/.../tiva-c_usb_host_cdc_driver

I used usbhcdc.c/h files and made source code like below.
(I want to attach my source code, but it seems not available here. If you need, I can send them via email.)
===============================================================
static void ConfigureIntUSB(void)
{
    /* Initialize the DSP interrupt controller */
    IntDSPINTCInit();
   
    /* Register ISR to vector table */
    IntRegister(C674X_MASK_INT5, USB0HostIntHandler);
   
    /* Map system interrupt to DSP maskable interrupt */
    IntEventMap(C674X_MASK_INT5, SYS_INT_USB0);
   
    /* Enable DSP maskable interrupt */
    IntEnable(C674X_MASK_INT5);
   
    /* Enable DSP interrupts */
    IntGlobalEnable();
}

int main(void)
{
 ............
 do
    {
        //
        //Setup the interrupt controller
        //
        ConfigureIntUSB();

        DelayTimerSetup();

        //
        // Enable Clocking to the USB controller.
        //
        PSCModuleControl(SOC_PSC_1_REGS,1, 0, PSC_MDCTL_NEXT_ENABLE);

        //USBStackModeSet(0, USB_MODE_HOST, NULL);

        //
        // Register the host class drivers.
        //
        USBHCDRegisterDrivers(USB_INSTANCE, g_ppHostClassDrivers, NUM_CLASS_DRIVERS);
  
  g_ulCDCInstance = USBHCDCDriveOpen(USB_INSTANCE, USBCDCCallback);
  
  USBHCDPowerConfigInit(USB_INSTANCE, USBHCD_VBUS_AUTO_HIGH);
  
          //
        // Initialize the host controller.
        //
        USBHCDInit(USB_INSTANCE, g_pHCDPool, HCD_MEMORY_SIZE);
        SET_CONNECT_RETRY (USB_INSTANCE, USBMSC_DRIVE_RETRY);
        USBHTimeOut->Value.slEP0 = USB_EP0_TIMEOUT_MILLISECS;
        USBHTimeOut->Value.slNonEP0= USB_NONEP0_TIMEOUT_MILLISECS;
        USBHCDTimeOutHook (USB_INSTANCE, &USBHTimeOut);
  
  while(1)
     {

      if(g_eState == STATE_DEVICE_ENUM)
      {
       if(USBHCDCReady(g_ulCDCInstance) == 0)
       {
     ret_size_s = 0;
     ret_size_s = USBHCDCWrite(g_ulCDCInstance, &ucChar_tx[0], 5);

     memset(ucChar_rx, 0x0, sizeof(ucChar_rx));
     ret_size = 0;

     //if(USBHCDCReady_read(g_ulCDCInstance) == 0)
     {
      ret_size = USBHCDCRead(g_ulCDCInstance, &ucChar_rx[0], sizeof(ucChar_rx));
      if(0 < ret_size)
       ret_size = 0;
     }
       }
      }

      if((USBHTimeOut->Status.slEP0)||
    (USBHTimeOut->Status.slNonEP0))
   {
    deviceRetryOnTimeOut--;
   }
   if(!deviceRetryOnTimeOut)
   {
    UARTprintf("%s\n", "Timedout too many times!!!");
    g_eState = STATE_TIMEDOUT;
    deviceRetryOnTimeOut = 4;

    USBHTimeOut->Value.slEP0 = USB_EP0_TIMEOUT_MILLISECS;
    USBHTimeOut->Value.slNonEP0= USB_NONEP0_TIMEOUT_MILLISECS;
    USBHTimeOut->Status.slEP0 = 0;
    USBHTimeOut->Status.slNonEP0= 0;
   }

   //
   // Periodically call the main loop for the Host controller driver.
   //
   //USBHCDMain();
   USBHCDMain (USB_INSTANCE, g_ulCDCInstance);
     }
    }while(1);
}
==============================================================
  
When I call USBHCDCWrite function, USBEndpointStatus() return USB_HOST_OUT_ERROR in USBHostIntHandlerInternal.

I'm trying to find some solution for it, but it seems very complicated.

Could you give me a hint to resolve this issue?
Any tips or help will be appreciated for me~!

Thanks~