Certainly you can
setInterval(function () {
var point = chart.series[0].points[0],
newVal,
inc = 0;
$.get('squaking', function (data) {
newVal = point.y + data.inc;
if (newVal < 0 || newVal > 20) {
newVal = point.y - data.inc;
}
point.update(newVal);
});
}, 3000);
I'm assuming here that "squaking" is a server side function that returns a JSON result containing a value for inc. Once the data is returned, the chart is then updated.