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MGTEVB

EventHdr

Documentation for architecture MGTEVB/EventHdr/a0

VHDL Contents

    1  -- EASE/HDL begin --------------------------------------------------------------
    2  -- 
    3  -- Architecture 'a0' of entity 'EventHdr'.
    4  -- 
    5  --------------------------------------------------------------------------------
    6  -- 
    7  -- Copy of the interface declaration:
    8  -- 
    9  --   port(
   10  --     Clk   : in     std_logic;
   11  --     FullX : in     std_logic;
   12  --     LWD   : in     std_logic_vector(31 downto 0);
   13  --     LWDEN : in     std_logic;
   14  --     LWX   : out    std_logic_vector(31 downto 0);
   15  --     LWXEN : out    std_logic;
   16  --     Rst_n : in     std_logic);
   17  -- 
   18  -- EASE/HDL end ----------------------------------------------------------------
   19  
   20  architecture a0 of EventHdr is
   21  
   22    constant Wrapcnt : std_logic_vector(11 downto 0) := x"002"; -- number of wrapper words
   23  
   24  begin
   25  
   26    pr1:
   27    process (Clk, Rst_n)
   28      variable wcnt : std_logic_vector(11 downto 0);
   29    begin
   30      if (Rst_n = '0') then
   31        LWX   <= (others => '0');
   32        LWXEN <= '0';
   33      elsif (rising_edge(Clk)) then
   34        if (LWDEN = '1') then
   35          case LWD(31 downto 24) is
   36          when x"8A" =>                   -- look for TWC word
   37            wcnt := LWD(11 downto 0) + Wrapcnt;
   38            --LWX <= LWD(31 downto 24) & LWD(23 downto 12) & wcnt;  -- send trailer
   39            LWX <= x"00" & LWD(23 downto 12) & wcnt;  -- zeroes & event-id & wcnt
   40            LWXEN <= '1';                 -- send final wordcount via extended data channel
   41          when others =>
   42            --LWX <= x"00000000";
   43            LWXEN <= '0';                 -- nothing to send
   44          end case;
   45        else
   46          LWXEN <= '0';
   47        end if;
   48      end if;
   49    end process;
   50  
   51  end architecture a0 ; -- of EventHdr
   52  
   53