I don't exactly understand the usage of the "filter". Should this be the trigger level?
Filter is used to avoid triggers generated by "noise"
For example in cases like this, if filter = 0 then it will trigger at the high frequency component of the signal.
If you set filter to a valule > amplitude of undesired signal, then it will triger by the low frequency component.
The exact point of the trigger depends on various things.
Might it be possible to have "a real" trigger level included (and named rabbit ) as a feature?
It would also be great to see it as e.g. an arrow in the scope screen (see mockup image below).
Addidionally another rotary knob as an input would be good.
Yes, something like this and some other trigger features are planned.
For example an option for rising/falling edge is missing now.
Triggers will have a separate "section" with options to configure it.
Perhaps similar to Logic Analizer, at the bottom, but not 100% sure yet.