Functions are part of the Building view.
A KNX installation can as such perfectly be set up without the Building view. It is however for 'organizational' reasons recommended to set up the Building view too, especially for larger installations.
The Building view decouples the topological location (= Individual Address) of the device from its physical location (= where is it mounted). I.e. it is possible to add devices to rooms, stairways, cabinets, etc. independently from the network topology. E.g. within a kitchen it is possible to add the kitchen specific functions.
A function collects Group Objects that 'belong' together.
- switching function = switching + status
- dimming function = switching + dimming + value + status
- blinds = movement + stop/step + wind alarm
ETS offers a number of predefined functions, and it is also possible to add 'custom' functions in order to set up any Group Object collection.