/*Generate an electronic ringer sound that quickly alternates between two frequencies*/
int index=0;
for(index=0; index<buf_size; ++index)
{
if(( index/(sample_rate )) %4<2 )//4 second ring cycle, first 2 secondsring, the rest(2 seconds) is silence
{
if((index/1000)%2==1 )
{
samples[index] = 5000 * sin( (2.0*3.1415926*frequency1)/sample_rate * index ); //5000=amplitude(volume level). It can be from zero to 32700
}
else
{
samples[index] = 5000 * sin( (2.0*3.1415926*frequency2)/sample_rate * index );
}
}
else
{
samples[index]=0;
}
}