Connector in oscope-1

Hello there, I'm just getting started with the simulIDE so i also have an absolute beginner's question, but why does the oscope-1 have the fifth port at the bottom?

Hi.

That's the reference pin, ussually ground.
But if for example you want your "zero" at 2.5V, then connect that pin to a 2.5V voltage source.

Thanks a lot for your fast response. Could you please answer me one more question: what is the filter entry for. I thought it was the trigger threshold, but that doesn't seem to be the case.

It filters out any voltage change below that value.
So small "peaks" are not considered part of the wave.