Programming a limit switch for two buttons

[TBots]

We have two buttons that allow the arms of our robot to move up and down a shaft. One moves up, and one moves down. How to we implement a limit switch so that the arms do not move too far down or too far up?

I've seen the examples from team 358, but they haven't been of much help. I really don't know what to put into the begin vi or the telop(if that's even where it goes).

How does the limit switch know when to stop? How to I put in a limit switch for code that already deviates between -1 and 1? Do I have to use an encoder to determine the rpm?

Thank you for any help you can give us