+===========+
+------------+  Init     |                                      
|  FCN=0     +===========+                                      
|  No Window                                       
|  No Bitmap                                                      
|                   +-------+           
|          +========+==+    | More Fragments                 
|          |           | <--+ ~~~~~~~~~~~~~~~~~~~~                          
+--------> |   Send    |      send Fragment (FCN=0)                            
           +===+=======+                                                                      
               |  last fragment
               |  ~~~~~~~~~~~~                               
               |  FCN = 1                               
               v  send fragment+RCS
           +============+                                             
           |    END     |                                             
           +============+