Best way to "background-loop"

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C#

Hey guys,
I'm currently programming around with the LogitechLCD-SDK, since my plan is to use the LogitechLCD in a bigger application. For those who don't know: The LogitechLCD is basically a little screen with a few buttons which is integrated in some keyboards. But as I'm almost finished with my little test-project, there is one problem I'm not able to solve on my own.
I've created a method which checks the state of the four buttons and performes the related actions. The "bigger application" runs in the background of the system, so I have to call the CheckButton-method pretty frequently somehow, without draining noticeable CPU-power. How do I do that? Google doesn't tell me a way which fits in my situation.
Thanks for your help anyway!