touchtone phone_number sound

str = '6142358970'; %% random phone number

fs = 8000; % sample frequency
tmax = 0.1; % tone duration

t = linspace(0,tmax,tmax*fs+1);
y = zeros(1,400);
for k=1:length(str);
    y = [y DTMF_key(str(k),t) zeros(1,800)];
end


sound(y,fs);
wavwrite(y,fs,'random.wav');