synth_filter.m

Often it is necessary to add some logical control to a MATLAB algorithm to allow the generated hardw

%       AccelDSP 8.1.1 build 690 Production, compiled Apr 26 2006 
% 
%    THIS IS UNPUBLISHED, LICENSED SOFTWARE THAT IS THE CONFIDENTIAL 
%        AND PROPRIETARY PROPERTY OF XILINX OR ITS LICENSORS 
% 
%     Copyright(c) Xilinx, Inc., 2000-2006, All Rights Reserved. 
%     Reproduction or reuse, in any form, without the explicit written 
%     consent of Xilinx, Inc., is strictly prohibited. 

function [FilterOut,valid] = synth_filter(FilterIn, coeff_in, start_load)
 
persistent coeff count loadc tap_delay
if isempty(coeff)
    coeff = zeros(1,32);
    count = 1;
    loadc = 0;
    tap_delay = zeros(1,length(coeff));
end
 
if start_load == 1
    coeff(count) = coeff_in;
    count = count + 1;
    loadc = 1;
    valid = 0;
elseif (loadc == 1) & (count < 32)
    coeff(count) = coeff_in;
    count = count + 1;
    valid = 0;
elseif (loadc == 1) & (count == 32)
    coeff(count) = coeff_in;
    tap_delay = zeros(1,length(coeff));
    count = 1;
    loadc = 0;
    valid = 1
else
    valid = 1;
end

% Perform sum of products
FilterOut = tap_delay * coeff(end:-1:1)';
 
% Shift tap delay line
tap_delay = [tap_delay(2:length(coeff)) FilterIn];