-------------------------------------------------------------------------------
-- Title       : test des filtres bas niveau
-- Project     : 
-------------------------------------------------------------------------------
-- File        : test_gradient.vhd
-- Author      :   <nouel@szut>
-- Company     : 
-- Last update : 1999/11/19
-- Platform    : 
-------------------------------------------------------------------------------
-- Description :
--
-- 
-------------------------------------------------------------------------------
-- Modification history :
-- 1999/10/11 : created
-------------------------------------------------------------------------------
LIBRARY ieee;
USE ieee.std_logic_1164.ALL;

ENTITY test_gradient IS
END test_gradient;

USE work.utils.ALL;

ARCHITECTURE par_constantes OF test_gradient IS

  COMPONENT dut 
    PORT (h : IN std_ulogic;  		-- horloge
	  init : IN std_ulogic;  	-- reset
	  pixel : IN natural RANGE 0 TO 255;
	  pix_calcul : OUT natural RANGE 0 TO 255;
	  ready_in : IN std_ulogic;  	-- protocole d'entree
	  ack_in : OUT std_ulogic;
	  ready_out : OUT std_ulogic;
	  ack_out : IN std_ulogic);
  END COMPONENT;

  SIGNAL h, h1, h2, init, ready_in, ack_in, ready_out, ack_out : std_ulogic;
  SIGNAL pixel, sortie : integer;       -- contrainte differree

  FOR d1 : dut
    USE ENTITY work.filtre(gradient);

  TYPE tableau IS ARRAY (natural RANGE <>) OF natural RANGE 0 TO 255;

  CONSTANT entrees : tableau := (12, 120, 5, 67, 10, 7, 116, 85, 27, 32, 255, 254, 253);
  CONSTANT result : tableau  := ( 21,45, 94);
  CONSTANT tcirc : time := 100 ns;    -- 10megaH
  CONSTANT t1 : time := 115 ns;    -- 10megaH
  CONSTANT t2 : time := 125 ns;    -- 10megaH
BEGIN  -- par_constantes

  d1: dut PORT MAP (h, init, pixel, sortie, ready_in,ack_in,ready_out, ack_out);

  init <= '1', '0' AFTER  (tcirc + 10 ns);

  pour_circ : horloge(h, tcirc , 0 ns);
  pour_entr: horloge(h1, t1, 33 ns);
  pour_sort: horloge( h2, t2, 8 ns);

  stimu : PROCESS (h1, init, ack_IN )
    VARIABLE i : natural;
  BEGIN  -- PROCESS stimu
    IF init = '1'  THEN -- asynchronous reset (active low)
      ready_IN <= '0';
      pixel <= 127; -- pas 0
      i := 1;  
    ELSIF ack_in = '1' THEN
      ready_IN <= '0';
    ELSIF front_descendant(h1)  THEN    -- front descendant
      pixel <= entrees(i);
      ready_IN <= '1';
      i := i+1;
      IF i = entrees'length THEN
        
        i:= 1;
      END IF;

    END IF;
  END PROCESS stimu;


  PROCESS 
  BEGIN  -- PROCESS
    FOR i IN result'range LOOP
      WAIT UNTIL front_montant(h2) ;
      IF ready_out = '1' THEN
        ASSERT sortie /= result(i) REPORT "test " & character'val(49+i) & " correct" SEVERITY warning;
      END IF;
      ack_OUT <= ready_out; -- recopie pour valider le protocole
    END LOOP;  -- i 
  END PROCESS;
END par_constantes;