fs=4e3;		% sampling frequency
f1=1270;
f0=1070;

t=1/fs:1/fs:5;

s1=0.99*sin(2*pi*f1*t);
s0=0.99*sin(2*pi*f0*t);

s=[s1 s0 s1 s0 s1 s1 s0 s0 s1 s0 s0 s1 s1 s1];

wavwrite(s, fs, 8, 'rs232.wav');
