Graph Unit Step

[Spilota]

I have a database that records the state of a variety of switches (light switches, sprinkler valves).  I am recording a datapoint for every state change.  So my dataset looks similar to this:

Time - State

8:00 - 0

9:00 - 0

10:00 - 1

11:00 - 0

12:00 - 0

13:00 - 1

14:00 - 1

15:00 - 0

This corresponds to a switch closing ('1') at 10 am and staying closed ('0') for an hour, then opening again for 2 hours at 1:00 pm.

I cannot figure out how to make this graph look like a step function.  I want to show a instantaneous state change at 10:00 am, instead of a sloped line from 9 - 10.