Knobs and menus
Controls that live on a circle. A knob is a body, ticks and an indicator that turns; a pie menu is a ring of clickable arcs. Use a continuous arc for values like gain, LEDs for discrete steps, and a pie menu when the choices fit around a point.
Knob with progress barA gain knob whose arc grows from the center.
LED knobEleven LEDs and a knob that snaps between them.
Pie menuWedges that open their options on an outer ring.
All three work with the pointer and the keyboard. Build a knob explains that part step by step, and the Kit knob and Kit menu come with it built in.