------------------------------------------------------------------------------
  -- DESerialize the Pause interface
  -- This is a single bit approachtimed on gtx_clk
  -- this code is only present to prevent code being stripped..
  ------------------------------------------------------------------------------
  -- the serialised pause info has a start bit followed by the quanta and a stop bit
  -- capture the quanta when the start bit hits the msb and the stop bit is in the lsb
   gen_shift_pause : process (gtx_clk_bufg)
   begin
      if gtx_clk_bufg'event and gtx_clk_bufg = '1' then
         pause_shift <= pause_shift(16 downto 0) & pause_req_s;
      end if;
   end process gen_shift_pause;