% create square wave


%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% x = square(t,duty cycle)
    % duty cycle = percentage of signal that's positive
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Fs = 44100;
dur = 1;
t = [0 : 1/Fs : dur-1/Fs];


freq = 400;

%%%%%%%%%
% square wave vector
fsq = .2* square ( 2*pi * freq * t, 50 );

% sound(fsq,Fs)

% plot 2 periods of square wave
plot( t(1 : round(2*1/freq*Fs)) , fsq(1 : round(2*1/freq*Fs)) )
axis([0 dur/round(2*1/freq*Fs) min(fsq)-.1 max(fsq)+.1 ])

% plot spectrogram of square wave
figure(2)
specgram(fsq,256,Fs)