Chebyshev filter design Problem

[Tahmod]

-I have design a chebyshev filter.With The following specification.
pass band 0-2khz
pass band ripple=0.5dB
sampling frequency 60khz
and the transfer function given which is :
H(s)=1.5161/(s^2+1.4526s+1.5161)

-When I have done the design by hand I done I got (bi-linear )
H(z)=(0.0143+0.029z^-1+0.0143z^-2)/(1-1.682z^-1+0.8695z^-2)

-The problem is when I put it in Matlab to check, I cant get the it working.
-What is the problem with the code?
-Do I have to use another function instead of cheb1ord to allow only the bandpass frequency and not the other one?
-The error says:
error using cheb1ord (line 62)
The cutoff frequencies must be non-negative for analog filters.

Error in chebyshevIIR (line 93)
[N,Wn]=cheb1ord(wpp,wss,ap,as,'s') %Until here it is write


-Code
Fp=2000;
Fs=0;
ap=0.5;
as=0;
Ft=60000; % Sampling frequency
wp=2*pi*Fp/Ft
ws=2*pi*Fs/Ft

wpp=tan(wp/2)
wss=tan(ws/2)
[N,Wn]=cheb1ord(wpp,wss,ap,as,'s')

[B,A]=cheby1(N,1,Wn,'s');
[BT,AT]=lp2hp(B,A,wpp);
[num,den]=bilinear(BT,AT,1/Ft);
tfHlp=tf(B,A) %Transfer function Glp(s) of the prototype analog lowpass filter
tfHhp=tf(BT,AT) %Transfer function Hhp(s) of the analog highpass filter
tfGhp=tf(num,den) %The transfer funcition Ghp(z) of the desired digital IIR highpass filter

 

[barry]

You've got Fs=0, that would imply a High-pass filter. Maybe 0 is not allowed? Also, you've got passband ripple as .5dB (I assume that's what ap is), and a stopband gain of 0dB. I'm not a matlab expert, but those values don't look right, if I'm interpreting stuff correctly.