filter impulse response problem

hello all , I need to implement CIC decimator, here is the matlab code using fvtool

    r=64;
m=1;
n=3;
iwl=16;
owl=12;
IFL  = 0; % Input fraction length
CIC = mfilt.cicdecim(r,m,n);
CIC.InputFracLength = IFL;
f_in =5120;
h=fvtool(CIC,'FS',f_in);

I checked the impulse response using the fvtool and it gives me a complete different response when using the following code:

     x= zeros(16*100,1,'int16'); x(1)=1;
     d=filter(CIC,x);
     stem(d);

what is the problem ? , when i used the HDL coder, the response of the verilog code is just like the 2nd case

please help me thank u