How can I use LPT-USB to trigger the output?

I have worked on some codes to filter the sound.

I asked few days ago if anybody knows how to turn LED light on by using LPT-USB port and MATLAB.. but nobody answered.

I have filtered the sound and have a frequency spectrum.

According to that specified frequency, I need to trigger the output with LPT-USB port.

Following is what I did so far.

 % Reading wav file

 b=wavread('/Users/*******/Desktop/traffichonk.wav');

 % Selecting a portion (37s to 41s)

 b1=b(44100*37:44100*41);

 size(b1)

 % FFT algorithm
 n=176401;
 fs=44100;
 ts2=1/fs;
 tmax2=(n-1)*ts2;
 t2=0:ts2:tmax2;
 f2=-fs/2:fs/(n-1):fs/2;
 z2=fftshift(fft(b1));

 % Plotting the sample b1
 figure(1)
 plot(t2,b1)
 title('Plot of a Sound Sample');
 xlabel('time(s)');
 ylabel('Sound data');

 % Plotting the Frequency Spectrum
 figure(2)
 plot(f2,abs(z2))
 title('Frequency Spectrum');
 xlabel('Frequency Hz');
 ylabel('Amplitude');

 % After bandpass toolbox is used, alert saying "The variable 'Hbp' has been
 % exported to the command window.' will show up.
 b2=filter(Hbp,b1);
 z3=fftshift(fft(b2));

 % Plotting the frequency spectrum after filtering
 figure(3)
 plot(f2,abs(z3))
 title('Frequency Spectrum after Filtering');
 xlabel('Frequency(Hz)');
 ylabel('Amplitude');

 % Checking the sound
 soundsc(b2,44100)

I need to take live input in and send live output out... and I will use a microphone for a input device and LPT to USB port...(I found some info online- people said I could use LPT port to get output signal but I don't know if LPT-USB port is the right one)

Anyway, triggering the output or code for LPT-USB port.. anything is fine.

Please I'll appreciate any help.

Thanks

[Walter Roberson]

How does this question differ from the previous one?

[Junghee]

Oh It's same :D nobody put answer on mine and it was gone from the first page so thought nobody will read mine

[Walter Roberson]

Duplicates http://www.mathworks.co.uk/matlabcentral/answers/108458-need-to-turn-led-lights-on-by-using-lpt-port-so-far-used-fft-and-bandpass-filter