KNX: Multiway Switching With Room Controller, Switch and Binary Input

If you’re controlling a group of lights from multiple different types of switches, you’ll run into the problem that a switch needs to be pressed twice - the first tap doesn’t have any effect. This happens because state is not maintained properly; the switches don’t “know” whether the lights are currently turned on or off. This article shows how to fix that.
KNX & ETS
