I discovered that on can expand functions in a DC or DCC board by adding i.e a lighting circuit board. What functions are F1 (Green) F2 (Violet) F3 (Brown) and F4 (White/Yellow) usually used for?
White is for the forward headlight, yellow is for the rear headlight and the purple and green can be used for additional lighting effects such as strobes, mars light, ditchlight, etc.