According to Drehscheibe, there were no Läutewerke or Läutebuden at unmanned Haltepunkte or Haltestellen. That makes sense, since they were intended for railway operations staff (level crossing keepers, pointsmen, signalmen).

Apart from the 3 types of Läutebude with one, two and three bells, and hence up to three different sounding rings, I assume the wall-mounted bells on station buildings had their own unique sound(s).

Paul, of (formerly Prussian-occupied) Lower Saxony