F2 = 5 %input('Message frequency = ');
t = 0:1/50:1;
x=0.75*5*sin(2*pi*F2*t); % Message signal
plot(t,x);
var=zeros(1,51);
for i=1:51
   var(i)=x(i);
end
id = fopen('D:\dsp\x.bin','wb');
fwrite(id, var,'double');
fclose(id);