iir_biquad.m

iir filter creat by altera

function y=iir_biquad(SecOrd, Inp);

w=zeros(1,min(length(Inp),300));
w_tmp=w;
y=zeros(1,min(length(Inp),300));
x=Inp;
SecOrd_scaled = round( SecOrd * 2^10); 
b1 = SecOrd_scaled(5);
b2 = SecOrd_scaled(6);
a0 = SecOrd_scaled(1);
a1 = SecOrd_scaled(2);
a2 = SecOrd_scaled(3);


for n=3:min(length(Inp),300)
    w_tmp(n) = ( b1 * w(n-1) ) + ( b2 * w(n-2) );
    w(n) =  x(n) - ( w_tmp(n) / 2^10 );
    y(n) = ( a0 * w(n) ) + ( a1 * w(n-1) ) + ( a2 * w(n-2) );
end
%y=y/(2^14);
%y=y';