From: analog_fever on
I am trying to see the response of a CIC filter for a set of input data.

I created the filter using the function

Hd = mfilt.cicdecim(100, 1, 3)
set(Hd, ...
'InputWordLength', 3, ...
'InputFracLength', 0, ...
'FilterInternals', 'FullPrecision');

I have some signed data in decimal in an input array 'x'. If I do,

y = filter(Hd, x)

1. I am getting all zeros in y
2. y is not the form of a vector, but has other data in it.

I am puzzled on why y has all zeros? Can somebody help?