I do not know it helps you but this is my code for real time data plotting.
/*Initial pane settings*/
pane.XAxis.Type = AxisType.Date;
pane.XAxis.Scale.Format = "dd/MM/yy\nH:mm:ss";
pane.XAxis.Scale.Min = (XDate)(DateTime.Now);
//Shows 25 seconds interval.
pane.XAxis.Scale.Max = (XDate)(DateTime.Now.AddSeconds(25));
pane.XAxis.Scale.MinorUnit = DateUnit.Second;
pane.XAxis.Scale.MajorUnit = DateUnit.Minute;
pane.XAxis.MajorTic.IsBetweenLabels = true;
pane.XAxis.MinorTic.Size = 5;
/*Real time plotting*/
XDate time = new XDate(DateTime.Now.ToOADate());
LineItem curve= curve= myPane.CurveList[0] as LineItem;
IPointListEdit list = list = curve.Points as IPointListEdit;
list.Add(time,data);
//Scale pane if current time is greater than the initial xScale.Max
Scale xScale = zgcMasterPane.MasterPane.PaneList[0].XAxis.Scale;
if (time.XLDate > xScale.Max)
{
xScale.Max = (XDate)(DateTime.Now.AddSeconds(5));
xScale.Min = (XDate)(DateTime.Now.AddSeconds(-20));
}