--==========================================================
-- Design units : MinMaxBehave (Entity,Architecture)
--
-- File name    : MinMax_Behave.vhd
--
-- Purpose      : Behavioral description as specification
--                of a MinMax-Circuit
--
-- Limitations  :
--
-- Library      : WORK
--
-- Dependencies :
--
-- Author       : Claus-Juergen Thomas, REFT
--
-- Simulator    : Synopsys V3.1a on SUN SPARCstation 10
--
-----------------------------------------------------------
-- Revision list
-- Version Author Date           Changes
--
-- v1.0    cjt    13.12.95       new
--=========================================================

LIBRARY ieee;
USE ieee.std_logic_1164.all;

ENTITY MinMaxBehave IS
  GENERIC(M: positive := 4);
  PORT(DataIn  : IN integer;
       Clear   : IN std_logic;
       Reset   : IN std_logic;
       Enable  : IN std_logic;
       Clk     : IN std_logic;
       DataOut : OUT integer);
END MinMaxBehave;

--===========================ARCHITECTURE=================

ARCHITECTURE Behavior OF MinMaxBehave IS
 
  BEGIN

    main : PROCESS(Clear,Enable,Reset,Clk)

    VARIABLE Minimum,Maximum,Last,MinMax,TempDataIn,TempDataOut,Sum: INTEGER;

    BEGIN

      IF Clear = '1' THEN 
        TempDataOut := 0;
        ELSE IF Enable = '0' THEN
          TempDataOut := Last;
          ELSE IF Reset = '1' THEN
            TempDataOut := TempDataIn;
          ELSE
            TempDataOut := MinMax;
          END IF;
        END IF;
      END IF;

      IF Reset = '0' AND Reset'event THEN

        Minimum := 2**16;
        Maximum := -2**16;

      END IF;

      IF Clk = '1' AND Clk'event THEN

        TempDataIn := DataIn;

        IF Enable='1' THEN
          Last := TempDataIn;
        END IF;

        IF Reset = '0' AND Clear = '0' AND Enable = '1' THEN

          IF TempDataIn < Minimum THEN
            Minimum := TempDataIn;
          END IF;

          IF TempDataIn > Maximum THEN
            Maximum := TempDataIn;
          END IF;

          -- Computation of mean value

          Sum := Minimum + Maximum;
          MinMax := Sum/2;
          TempDataOut := MinMax;

        END IF;

      END IF;

    DataOut <= TempDataOut;

    END PROCESS;

END Behavior;