Subversion Repositories gnextrapolator

--//// This file is part of the GNExtrapolator project                          ////

--//// http://opencores.org/project,gnextrapolator                                      ////

--////                                                                                                                          ////

--//// Description                                                                                                      ////

--//// Implementation of Algoritm for extrapolation functions       ////

--////                                                                                                                          ////

--////                                                                                                                          ////

--//// To Do:                                                                                                           ////

--//// -                                                                                                                        ////

--////                                                                                                                          ////

--//// Author(s):                                                                                                       ////

--//// - Rodrigo Villegas, ruyvillegas@gmail.com, designer          ////

--//// - Iván Millán, ivanmillan36@gmail.com, designer                          ////

--//// - Pablo A. Salvadeo,     pas.@opencores, manager                                 ////

--////                                                                                                                          ////

--//////////////////////////////////////////////////////////////////////

--////                                                                                                                          ////

--//// Copyright (C) 2011 Authors and OPENCORES.ORG                             ////

--////                                                                                                                          ////

--//// This source file may be used and distributed without             ////

--//// restriction provided that this copyright statement is not        ////

--//// removed from the file and that any derivative work contains      ////

--//// the original copyright notice and the associated disclaimer.     ////

--////                                                                                                                          ////

--//// This source file is free software; you can redistribute it       ////

--//// and/or modify it under the terms of the GNU Lesser General       ////

--//// Public License as published by the Free Software Foundation;     ////

--//// either version 2.1 of the License, or (at your option) any       ////

--//// later version.                                                                                           ////

--////                                                                                                                          ////

--//// This source is distributed in the hope that it will be           ////

--//// useful, but WITHOUT ANY WARRANTY; without even the implied       ////

--//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR          ////

--//// PURPOSE. See the GNU Lesser General Public License for more      ////

--//// details.                                                                                                         ////

--////                                                                                                                          ////

--//// You should have received a copy of the GNU Lesser General        ////

--//// Public License along with this source; if not, download it       ////

--//// from http://www.opencores.org/lgpl.shtml                                         ////

--////                                                                                                                          ////

--//////////////////////////////////////////////////////////////////////

LIBRARY ieee;

USE ieee.std_logic_1164.all;

USE ieee.std_logic_signed.all;

USE ieee.std_logic_arith.all;

entity gnextrapolator is

        port

        (

                rst_i   : in  std_logic;

                clk_i   : in  std_logic;

                distancia_i:    in std_logic_vector(7 downto 0);

                extrapolar_i:   in std_logic;

                indice_p_o:             out std_logic_vector(4 downto 0);

                fxx_o:          out std_logic_vector(15 downto 0);

                fxx1_o:         out std_logic_vector(15 downto 0);

                fxx2_o:         out std_logic_vector(15 downto 0);

                fxx3_o:         out std_logic_vector(15 downto 0);

                fxx4_o:         out std_logic_vector(15 downto 0);

                resul_o:        out std_logic_vector(15 downto 0)

        );

end gnextrapolator;

architecture grenew of gnextrapolator is

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

type columna is array(0 to 2) of std_logic_vector(15 downto 0);

signal sfx:             columna;

signal indice:  integer range 0 to 31;

signal sram:    std_logic_vector(15 downto 0);

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

        subtype word_t is std_logic_vector(15 downto 0);

        type memory_t is array(0 to 31) of word_t;

        signal ram : memory_t;

        attribute romstyle :                    string;

        attribute romstyle of ram :     signal is "M512";

        attribute ram_init_file :               string;

        attribute ram_init_file of ram :signal is "gnextrapolator.mif";

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

begin

process(rst_i,clk_i)

variable i:integer range 0 to 2 ;

variable resultado:std_logic_vector(15 downto 0);

variable fx: columna;

variable nabla1fx: columna;

variable nabla2fx: columna;

variable nabla3fx: columna;

variable nabla4fx: columna;

variable compensacion: columna;

variable cont:integer range 0 to 65535;

begin

if (rst_i='1') then

        i:=0;

        cont:=0;

        fx(0):= (others=>'0');

        nabla1fx(0):= (others=>'0');

        nabla2fx(0):= (others=>'0');

        nabla3fx(0):= (others=>'0');

        nabla4fx(0):= (others=>'0');

        indice<=0;

elsif(rising_edge(clk_i)) then

        if(extrapolar_i = '0') then

        fx(i):= sram;

                                                                                --

                                                                                -- Se resiben los datos hasta que se ponga en alto el pin

        elsif(extrapolar_i = '1') then          -- 'extrapolar', con lo cual, se comienza a usar como valores

        fx(i):=resultado;                                       --

        cont:= cont+1;                                          -- de la funcion los resultados calculados, y se deja de tomar datos

        end if;                                                         -- de la entrada.

        nabla1fx(i):=(fx(i)-fx(i-1));                                                                           -- Se calculan los nablas y el resultado

        nabla2fx(i):=(nabla1fx(i)-nabla1fx(i-1));                                                       -- de sumar la ultima fila de vaores de

        nabla3fx(i):=(nabla2fx(i)-nabla2fx(i-1));                                                       -- la tabla.

        nabla4fx(i):=(nabla3fx(i)-nabla3fx(i-1));                                                       --

                                                                                                                                                --

        resultado:=fx(i)+nabla1fx(i)+nabla2fx(i)+nabla3fx(i)+nabla4fx(i);       --

        fxx_o   <=        fx(i);                                  --

        fxx1_o<=        nabla1fx(i);                    -- Se envian los datos a salidas para su observacion,

        fxx2_o<=        nabla2fx(i);                    -- el resultado se envia cada cierta cantidad de muestras

        fxx3_o<=        nabla3fx(i);                    -- definida por el usuario.

        fxx4_o<=        nabla4fx(i);                    --

        if(cont = distancia_i) then     --

        resul_o<=resultado;                     --

        cont:=0;                                        --

        end if;                                         --

        fx(0):=                 fx(i);                  -- se desplaza la fila hacia atras para poder calcular la siguiente

        nabla1fx(0):=   nabla1fx(i);    --

        nabla2fx(0):=   nabla2fx(i);    --

        nabla3fx(0):=   nabla3fx(i);    --

        nabla4fx(0):=   nabla4fx(i);    --

i:=1;

indice <= indice+1;

end if;

end process;

indice_p_o <= std_logic_vector(to_signed(indice));

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

process(clk_i)

        begin

        if(falling_edge(clk_i)) then

               sram <= ram(indice);

        end if;

end process;

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

end grenew;