waveform in prototype functions?

Oh, I just looked again - and you're just creating a Waveform, not doing anything, and then reading back the values. It's not really surprising the array is just full of 0?

What about doing what's described on the waveform page, and using the finish event?

var w = new Waveform(128);
w.on("finish", function(buf) {  //<----------- this
  // your temperature reading code
});
w.startInput(A0,2000,{repeat:false});