Subversion Repositories lpffir

% //////////////////////////////////////////////////////////////////////

% ////                                                              ////

% ////  Low Pass Filter FIR IP Core                                 ////

% ////                                                              ////

% ////  This file is part of the LPFFIR project                     ////

% ////  https://opencores.org/projects/lpffir                       ////

% ////                                                              ////

% ////  Description                                                 ////

% ////  Implementation of LPFFIR IP core according to               ////

% ////  LPFFIR IP core specification document.                      ////

% ////                                                              ////

% ////  To Do:                                                      ////

% ////  -                                                           ////

% ////                                                              ////

% ////  Author:                                                     ////

% ////  - Vladimir Armstrong, vladimirarmstrong@opencores.org       ////

% ////                                                              ////

% //////////////////////////////////////////////////////////////////////

% ////                                                              ////

% //// Copyright (C) 2019 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                     ////

% ////                                                              ////

% //////////////////////////////////////////////////////////////////////

% Cleanup

clear;clc;close all;

% Difference equation of low-pass filter

b = [1, 1, 1, 1, 1, 1]; a = [1];

% Response

n = [0:7];

h = impz(b,a,8);

[H,w] = freqz(b,a,100);

magH = abs(H); phaH = angle(H);

% Plot

subplot(4,1,1); stem(n,h);

title('Impulse Response'); xlabel('n'); ylabel('h(n)')

subplot(4,1,2);zplane(b,a);grid

title('Pole-Zero Plot')

subplot(4,1,3);plot(w/pi,magH);grid

xlabel('Frequency in \pi units'); ylabel('Magnitude');

title('Magnitude Response')

subplot(4,1,4);plot(w/pi,phaH/pi);grid

xlabel('Frequency in \pi units'); ylabel('Phase in \pi units');

title('Phase Response')

% Write Tabular Impulse Response Data to Text File

fileID = fopen('matlab_impulseResponse.txt','w');

fprintf(fileID,'%1.1d\n',h);

fclose(fileID);