How do I overlay a theoretical square wave on sensor data in Excel?

[mpm166]

I have collected 5000 points of data from a sensor on a rotary arm (which I was trying to control to move with a position time graph that follows the pattern of a square wave)

My question is, once I've plotted the graph in excel, how can I overlay a perfect (theoretical) square wave to show the discrepencancies in the collected data from the desired setpoint?

 

[enigma]

Do you know the position vs. time data for the perfect square wave?

Enter them into excel, and create a second data series on the same chart.