KLMReadoutTrg.vhd

library ieee;
   use ieee.std_logic_1164.all;
   use ieee.numeric_std.all;
   use ieee.std_logic_unsigned.all;
   use ieee.std_logic_misc.all;
library work;
   use work.klm_scint_pkg.all;


entity KLMReadoutTrg is
   port (
      clk          : in  std_logic;
      rst          : in  std_logic;
                  
      trg          : in  std_logic;
      ctime        : in  std_logic_vector(26 downto 0);
      trgtag       : in  std_logic_vector(4 downto 0);
      readout_busy : in  std_logic;
                  
      localtrg     : out std_logic;
      ctime_trg    : out std_logic_vector(26 downto 0); 
      -- trgtag_trg   : out std_logic_vector( 3 downto 0);

      trg_cnt      : out std_logic_vector(15 downto 0)
   );
end entity KLMReadoutTrg;

architecture behav of KLMReadoutTrg is
   
   signal i_localtrg      : std_logic := '0';

   --- trigger fifo signals
   signal i_trgfifo_din   : std_logic_vector(31 downto 0);
   signal i_trgfifo_wen   : std_logic;
   signal i_trgfifo_ren   : std_logic;
   signal i_trgfifo_dout  : std_logic_vector(31 downto 0);
   -- signal i_trgfifo_full  : std_logic;
   signal i_trgfifo_empty : std_logic;

   -- counters
   signal i_trg_cnt       : std_logic_vector(15 downto 0) := (others => '0');
   

begin

   ------------------------------------------------
   --- FIFO for TRG data 
   ------------------------------------------------
   trgfifo_i : entity work.fifo_cc
   generic map(
      DATA_WIDTH => 32,
      DEPTH      => 8   
   )
   port map (
      clk    => clk,
      rst    => rst,
      din    => i_trgfifo_din,
      wen    => i_trgfifo_wen,
      ren    => i_trgfifo_ren,
      dout   => i_trgfifo_dout,
      full   => open,
      empty  => i_trgfifo_empty
   );

   i_trgfifo_ren <= i_localtrg;
   i_trgfifo_din(26 downto 0)  <= ctime;
   i_trgfifo_din(31 downto 27) <= trgtag(4 downto 0);
   i_trgfifo_wen  <= trg;

   process (clk)
   begin
      if rising_edge (clk) then
         if rst = '1' then
            ctime_trg <= (others => '0');
            -- trgtag_trg <= (others => '0');
         else 
            i_localtrg <= '0';
            if i_trgfifo_empty = '0' and readout_busy = '0' and i_localtrg = '0' then
               i_localtrg <= '1';
               ctime_trg  <= i_trgfifo_dout(26 downto 0);
               -- trgtag_trg <= i_trgfifo_dout(30 downto 27); 
            end if;
         end if;
      end if;
   end process;
   localtrg <= i_localtrg;

   ------------------------------------------------

   ------------------------------------------------
   -- count incomming triggers 
   ------------------------------------------------
   TRGCNT_PROC : process(clk, rst)
   begin
      if rst = '1' then
         i_trg_cnt <= (others => '0');
      elsif rising_edge(clk) then
         if trg = '1' then
            i_trg_cnt <= i_trg_cnt + 1;
         end if;
      end if;
   end process TRGCNT_PROC;
   
   trg_cnt      <= i_trg_cnt;
   ------------------------------------------------

end behav;