{
      data_to_transfer = (U8)wLength;         //!< send only requested number of data
   }

   while((data_to_transfer != 0) && (!Is_usb_receive_out()))
   {
      while(!Is_usb_read_control_enabled());

      nb_byte=0;
      while(data_to_transfer != 0)        //!< Send data until necessary
      {
         if(nb_byte++==EP_CONTROL_LENGTH) //!< Check endpoint 0 size
         {
            break;
         }
#ifndef AVRGCC
         Usb_write_byte(*pbuffer++);
#else    // AVRGCC does not support point to PGM space
#warning with avrgcc assumes devices descriptors are stored in the lower 64Kbytes of on-chip flash memory
         Usb_write_byte(pgm_read_byte_near((unsigned int)pbuffer++));
#endif
         data_to_transfer --;
      }
      Usb_send_control_in();
   }


   if(Is_usb_receive_out()) { Usb_ack_receive_out(); return; } //!< abort from Host
   if(zlp == TRUE)
   {
     while(!Is_usb_read_control_enabled());
     Usb_send_control_in();
   }


   while(!Is_usb_receive_out());
   Usb_ack_receive_out();
}


//! usb_get_configuration.
//!
//! This function manages the GET CONFIGURATION request. The current
//! configuration number is returned.
//!
//! @warning Code:xx bytes (function code length)
//!
//! @param none
//!
//! @return none
//!
void usb_get_configuration(void)
{
   Usb_ack_receive_setup();

   Usb_write_byte(usb_configuration_nb);
   Usb_ack_in_ready();

   while( !Is_usb_receive_out() );
   Usb_ack_receive_out();
}

//! usb_get_status.
//!
//! This function manages the GET STATUS request. The device, interface or
//! endpoint status is returned.
//!
//! @warning Code:xx bytes (function code length)
//!
//! @param none
//!
//! @return none
//!
void usb_get_status(void)
{
U8 wIndex;
U8 dummy;

   dummy    = Usb_read_byte();                 //!< dummy read
   dummy    = Usb_read_byte();                 //!< dummy read
   wIndex = Usb_read_byte();

   switch(bmRequestType)
   {
    case REQUEST_DEVICE_STATUS:    Usb_ack_receive_setup();
                                   Usb_write_byte(DEVICE_STATUS);
                                   break;

    case REQUEST_INTERFACE_STATUS: Usb_ack_receive_setup();
                                   Usb_write_byte(INTERFACE_STATUS);
                                   break;

    case REQUEST_ENDPOINT_STATUS:  Usb_ack_receive_setup();
                                   wIndex = wIndex & MSK_EP_DIR;
                                   Usb_write_byte(endpoint_status[wIndex]);
                                   break;
    default:
                                   Usb_enable_stall_handshake();
                                   Usb_ack_receive_setup();
                                   return;
   }

   Usb_write_byte(0x00);
   Usb_send_control_in();

   while( !Is_usb_receive_out() );
   Usb_ack_receive_out();
}


//! usb_set_feature.
//!
//! This function manages the SET FEATURE request. The USB test modes are
//! supported by this function.
//!
//! @warning Code:xx bytes (function code length)
//!
//! @param none
//!
//! @return none
//!
void usb_set_feature(void)
{
U8 wValue;
U8 wIndex;
U8 dummy;

   if (bmRequestType == INTERFACE_TYPE)
   {
      //!< keep that order (set StallRq/clear RxSetup) or a
      //!< OUT request following the SETUP may be acknowledged
      Usb_enable_stall_handshake();
      Usb_ack_receive_setup();
      return;
   }
   else if (bmRequestType == ENDPOINT_TYPE)
   {
      wValue = Usb_read_byte();
      dummy    = Usb_read_byte();                //!< dummy read

      if (wValue == FEATURE_ENDPOINT_HALT)
      {
         wIndex = (Usb_read_byte() & MSK_EP_DIR);

         if (wIndex == EP_CONTROL)
         {
            Usb_enable_stall_handshake();
            Usb_ack_receive_setup();
            return;
         }

         Usb_select_endpoint(wIndex);
         if(Is_usb_endpoint_enabled())
         {
            Usb_enable_stall_handshake();
            Usb_select_endpoint(EP_CONTROL);
            endpoint_status[wIndex] = 0x01;
            Usb_ack_receive_setup();
            Usb_send_control_in();
         }
         else
         {
            Usb_select_endpoint(EP_CONTROL);
            Usb_enable_stall_handshake();
            Usb_ack_receive_setup();
            return;
         }
      }
      else
      {
         Usb_enable_stall_handshake();
         Usb_ack_receive_setup();
         return;
      }
   }
}


//! usb_clear_feature.
//!
//! This function manages the SET FEATURE request.
//!
//! @warning Code:xx bytes (function code length)
//!
//! @param none
//!
//! @return none
//!
void usb_clear_feature(void)
{
U8 wValue;
U8 wIndex;
U8 dummy;

   if (bmRequestType == ZERO_TYPE)
   {
      //!< keep that order (set StallRq/clear RxSetup) or a
      //!< OUT request following the SETUP may be acknowledged
      Usb_enable_stall_handshake();
      Usb_ack_receive_setup();
      return;
   }
   else if (bmRequestType == INTERFACE_TYPE)
   {
      //!< keep that order (set StallRq/clear RxSetup) or a
      //!< OUT request following the SETUP may be acknowledged
      Usb_enable_stall_handshake();
      Usb_ack_receive_setup();
      return;
   }
   else if (bmRequestType == ENDPOINT_TYPE)
   {
      wValue = Usb_read_byte();
      dummy  = Usb_read_byte();                //!< dummy read

      if (wValue == FEATURE_ENDPOINT_HALT)
      {
         wIndex = (Usb_read_byte() & MSK_EP_DIR);

         Usb_select_endpoint(wIndex);
         if(Is_usb_endpoint_enabled())
         {
            if(wIndex != EP_CONTROL)
            {
               Usb_disable_stall_handshake();
               Usb_reset_endpoint(wIndex);
               Usb_reset_data_toggle();
            }
            Usb_select_endpoint(EP_CONTROL);
            endpoint_status[wIndex] = 0x00;
            Usb_ack_receive_setup();
            Usb_send_control_in();
         }
         else
         {
            Usb_select_endpoint(EP_CONTROL);
            Usb_enable_stall_handshake();
            Usb_ack_receive_setup();
            return;
         }
      }
      else
      {
         Usb_enable_stall_handshake();
         Usb_ack_receive_setup();
         return;
      }
   }
}



//! usb_get_interface.
//!
//! TThis function manages the GET_INTERFACE request.
//!
//! @warning Code:xx bytes (function code length)
//!
//! @param none
//!
//! @return none
//!
void usb_get_interface (void)
{
  Usb_enable_stall_handshake();
  Usb_ack_receive_setup();
}

//! usb_set_interface.
//!
//! TThis function manages the SET_INTERFACE request.
//!
//! @warning Code:xx bytes (function code length)
//!
//! @param none
//!
//! @return none
//!
void usb_set_interface (void)
{
  Usb_ack_receive_setup();
  Usb_send_control_in();                    //!< send a ZLP for STATUS phase
  while(!Is_usb_in_ready());
}