usb - device not recognised

[mpardinho]

my code, create by easyhid

DEFINE OSC 48          
DEFINE LOADER_USED 1

USBBufferSizeMax   con 8  ' maximum buffer size
USBBufferSizeTX    con 8  ' input 
USBBufferSizeRX    con 8  ' output

' the USB buffer...
USBBuffer        Var Byte[USBBufferSizeMax] 
USBBufferCount   Var Byte 

' ************************************************************
' * main program loop - remember, you must keep the USB      *
' * connection alive with a call to USBService every couple  *
' * of milliseconds or so...                                 *
' ************************************************************
usbinit ' initialise USB...
ProgramStart: 
   gosub DoUSBIn
   gosub DoUSBOut
   goto ProgramStart  

' ************************************************************
' * receive data from the USB bus                            *
' ************************************************************
DoUSBIn:
   USBBufferCount = USBBufferSizeRX              ' RX buffer size
   USBService                                    ' keep connection alive
   USBIn 1, USBBuffer, USBBufferCount, DoUSBIn   ' read data, if available
   return
    
' ************************************************************
' * wait for USB interface to attach                         *
' ************************************************************
DoUSBOut:
   USBBufferCount = USBBufferSizeTX              ' TX buffer size
   USBService                                    ' keep connection alive
   USBOut 1, USBBuffer, USBBufferCount, DoUSBOut ' if bus available, transmit data
   return

i tryied cristal 20mhz or 8mhz and "device not recognised",
with 48 not detect

i tested demo program usbcdc and too "device not recognised".