filter.vhd

用verilog实现滤波器的功能

-- -------------------------------------------------------------
--
-- Module: filter
--
-- Generated by MATLAB(R) 7.0.4 and the Filter Design HDL Coder 1.2.
--
-- Generated on: 2005-11-03 18:55:40
--
-- -------------------------------------------------------------

-- -------------------------------------------------------------
-- HDL Code Generation Options:
--
-- TargetLanguage: VHDL
-- AddInputRegister: Off
-- TestBenchStimulus: impulse step ramp chirp noise 
--
-- Filter Settings:
--
-- Discrete-Time FIR Filter (real)
-- -------------------------------
-- Filter Structure  : Direct-Form FIR
-- Filter Length     : 51
-- Stable            : Yes
-- Linear Phase      : Yes (Type 1)
-- Arithmetic        : fixed
-- Numerator         : s16,16 -> [-5.000000e-001 5.000000e-001)
-- Input             : s16,15 -> [-1 1)
-- Filter Internals  : Specify Precision
--   Output          : s16,31 -> [-1.525879e-005 1.525879e-005)
--   Product         : s32,31 -> [-1 1)
--   Accumulator     : s40,31 -> [-256 256)
--   Round Mode      : floor
--   Overflow Mode   : saturate
-- -------------------------------------------------------------
LIBRARY IEEE;
USE IEEE.std_logic_1164.all;
USE IEEE.numeric_std.ALL;

ENTITY filter IS
   PORT( clk                             :   IN    std_logic; 
         clk_enable                      :   IN    std_logic; 
         reset                           :   IN    std_logic; 
         filter_in                       :   IN    std_logic_vector(15 DOWNTO 0); -- sfix16_En15
         filter_out                      :   OUT   std_logic_vector(15 DOWNTO 0)  -- sfix16_En31
         );

END filter;


----------------------------------------------------------------
--Module Architecture: filter
----------------------------------------------------------------
ARCHITECTURE rtl OF filter IS
  -- Local Functions
  -- Type Definitions
  TYPE delay_pipeline_type IS ARRAY (NATURAL range <>) OF signed(15 DOWNTO 0); -- sfix16_En15
  -- Constants
  CONSTANT coeff1                         : signed(15 DOWNTO 0) := to_signed(-60, 16); -- sfix16_En16
  CONSTANT coeff2                         : signed(15 DOWNTO 0) := to_signed(-178, 16); -- sfix16_En16
  CONSTANT coeff3                         : signed(15 DOWNTO 0) := to_signed(-163, 16); -- sfix16_En16
  CONSTANT coeff4                         : signed(15 DOWNTO 0) := to_signed(240, 16); -- sfix16_En16
  CONSTANT coeff5                         : signed(15 DOWNTO 0) := to_signed(895, 16); -- sfix16_En16
  CONSTANT coeff6                         : signed(15 DOWNTO 0) := to_signed(1137, 16); -- sfix16_En16
  CONSTANT coeff7                         : signed(15 DOWNTO 0) := to_signed(502, 16); -- sfix16_En16
  CONSTANT coeff8                         : signed(15 DOWNTO 0) := to_signed(-430, 16); -- sfix16_En16
  CONSTANT coeff9                         : signed(15 DOWNTO 0) := to_signed(-504, 16); -- sfix16_En16
  CONSTANT coeff10                        : signed(15 DOWNTO 0) := to_signed(400, 16); -- sfix16_En16
  CONSTANT coeff11                        : signed(15 DOWNTO 0) := to_signed(909, 16); -- sfix16_En16
  CONSTANT coeff12                        : signed(15 DOWNTO 0) := to_signed(23, 16); -- sfix16_En16
  CONSTANT coeff13                        : signed(15 DOWNTO 0) := to_signed(-1108, 16); -- sfix16_En16
  CONSTANT coeff14                        : signed(15 DOWNTO 0) := to_signed(-584, 16); -- sfix16_En16
  CONSTANT coeff15                        : signed(15 DOWNTO 0) := to_signed(1143, 16); -- sfix16_En16
  CONSTANT coeff16                        : signed(15 DOWNTO 0) := to_signed(1360, 16); -- sfix16_En16
  CONSTANT coeff17                        : signed(15 DOWNTO 0) := to_signed(-806, 16); -- sfix16_En16
  CONSTANT coeff18                        : signed(15 DOWNTO 0) := to_signed(-2244, 16); -- sfix16_En16
  CONSTANT coeff19                        : signed(15 DOWNTO 0) := to_signed(-68, 16); -- sfix16_En16
  CONSTANT coeff20                        : signed(15 DOWNTO 0) := to_signed(3132, 16); -- sfix16_En16
  CONSTANT coeff21                        : signed(15 DOWNTO 0) := to_signed(1793, 16); -- sfix16_En16
  CONSTANT coeff22                        : signed(15 DOWNTO 0) := to_signed(-3891, 16); -- sfix16_En16
  CONSTANT coeff23                        : signed(15 DOWNTO 0) := to_signed(-5394, 16); -- sfix16_En16
  CONSTANT coeff24                        : signed(15 DOWNTO 0) := to_signed(4403, 16); -- sfix16_En16
  CONSTANT coeff25                        : signed(15 DOWNTO 0) := to_signed(20317, 16); -- sfix16_En16
  CONSTANT coeff26                        : signed(15 DOWNTO 0) := to_signed(28184, 16); -- sfix16_En16
  CONSTANT coeff27                        : signed(15 DOWNTO 0) := to_signed(20317, 16); -- sfix16_En16
  CONSTANT coeff28                        : signed(15 DOWNTO 0) := to_signed(4403, 16); -- sfix16_En16
  CONSTANT coeff29                        : signed(15 DOWNTO 0) := to_signed(-5394, 16); -- sfix16_En16
  CONSTANT coeff30                        : signed(15 DOWNTO 0) := to_signed(-3891, 16); -- sfix16_En16
  CONSTANT coeff31                        : signed(15 DOWNTO 0) := to_signed(1793, 16); -- sfix16_En16
  CONSTANT coeff32                        : signed(15 DOWNTO 0) := to_signed(3132, 16); -- sfix16_En16
  CONSTANT coeff33                        : signed(15 DOWNTO 0) := to_signed(-68, 16); -- sfix16_En16
  CONSTANT coeff34                        : signed(15 DOWNTO 0) := to_signed(-2244, 16); -- sfix16_En16
  CONSTANT coeff35                        : signed(15 DOWNTO 0) := to_signed(-806, 16); -- sfix16_En16
  CONSTANT coeff36                        : signed(15 DOWNTO 0) := to_signed(1360, 16); -- sfix16_En16
  CONSTANT coeff37                        : signed(15 DOWNTO 0) := to_signed(1143, 16); -- sfix16_En16
  CONSTANT coeff38                        : signed(15 DOWNTO 0) := to_signed(-584, 16); -- sfix16_En16
  CONSTANT coeff39                        : signed(15 DOWNTO 0) := to_signed(-1108, 16); -- sfix16_En16
  CONSTANT coeff40                        : signed(15 DOWNTO 0) := to_signed(23, 16); -- sfix16_En16
  CONSTANT coeff41                        : signed(15 DOWNTO 0) := to_signed(909, 16); -- sfix16_En16
  CONSTANT coeff42                        : signed(15 DOWNTO 0) := to_signed(400, 16); -- sfix16_En16
  CONSTANT coeff43                        : signed(15 DOWNTO 0) := to_signed(-504, 16); -- sfix16_En16
  CONSTANT coeff44                        : signed(15 DOWNTO 0) := to_signed(-430, 16); -- sfix16_En16
  CONSTANT coeff45                        : signed(15 DOWNTO 0) := to_signed(502, 16); -- sfix16_En16
  CONSTANT coeff46                        : signed(15 DOWNTO 0) := to_signed(1137, 16); -- sfix16_En16
  CONSTANT coeff47                        : signed(15 DOWNTO 0) := to_signed(895, 16); -- sfix16_En16
  CONSTANT coeff48                        : signed(15 DOWNTO 0) := to_signed(240, 16); -- sfix16_En16
  CONSTANT coeff49                        : signed(15 DOWNTO 0) := to_signed(-163, 16); -- sfix16_En16
  CONSTANT coeff50                        : signed(15 DOWNTO 0) := to_signed(-178, 16); -- sfix16_En16
  CONSTANT coeff51                        : signed(15 DOWNTO 0) := to_signed(-60, 16); -- sfix16_En16

  -- Signals
  SIGNAL delay_pipeline                   : delay_pipeline_type(0 TO 49); -- sfix16_En15
  SIGNAL filter_in_regtype                : signed(15 DOWNTO 0); -- sfix16_En15
  SIGNAL product51                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product50                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product49                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product48                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product47                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product46                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product45                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product44                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product43                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product42                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product41                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product40                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product39                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product38                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product37                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product36                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product35                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product34                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product33                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product32                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product31                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product30                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product29                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product28                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product27                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product26                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product25                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product24                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product23                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product22                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product21                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product20                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product19                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product18                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product17                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product16                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product15                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product14                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product13                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product12                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product11                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product10                        : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product9                         : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product8                         : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product7                         : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product6                         : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product5                         : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product4                         : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product3                         : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product2                         : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL product1                         : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL mul_temp                         : signed(31 DOWNTO 0); -- sfix32_En31
  SIGNAL sum1                             : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp                         : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum2                             : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_1                       : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum3                             : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_2                       : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum4                             : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_3                       : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum5                             : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_4                       : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum6                             : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_5                       : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum7                             : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_6                       : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum8                             : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_7                       : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum9                             : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_8                       : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum10                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_9                       : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum11                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_10                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum12                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_11                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum13                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_12                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum14                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_13                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum15                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_14                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum16                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_15                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum17                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_16                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum18                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_17                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum19                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_18                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum20                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_19                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum21                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_20                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum22                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_21                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum23                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_22                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum24                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_23                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum25                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_24                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum26                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_25                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum27                            : signed(39 DOWNTO 0); -- sfix40_En31
  SIGNAL add_temp_26                      : signed(40 DOWNTO 0); -- sfix41_En31
  SIGNAL sum28                            : signed(39 DOWNTO 0); -- sfix40_En31