Using the Solid line

Hello everybody,

I would like to use a solid line to plot a pulse. In other words let's say I have a number of zeros and ones
and I would like to connect them like this with solid lines:

------- +-------
  + + +
  +------- ----------

Of course when I use the plot() function with the formater "-" , it connects the points differently. Is there a
way to override this default action? Thank you very much.

            Panos