Serial communication between Espruino and Arduino for 433mhz OOK transmit/receive.

Well, there's:

SerialX.on('data', function(s) {
  s.split("").forEach(obj.onData);
});

But what I tend to do is handle a line at a time, which I think is easier?

var line = "";
SerialX.on('data', function(s) {
  line += s;
  var i = line.indexOf("\n");
  while (i>=0) {
    handleLine(line.substr(0,i));
    line = line.substr(i+1);
    i = line.indexOf("\n");
  }
});