marcdahl.dk

If you work with modern building automation, you know that bridging the gap between a technical backend and a sleek, user-friendly frontend can sometimes require a little bit of custom engineering. Recently, I was looking for a flawless way to control DALI2 DT8 RGBW luminaires through a graphical interface. Specifically, I needed a solution for Node-RED Dashboard 2.0 that communicates directly with the KNX Ultimate node using the 6-byte combined group object (DPT 251.600 Color Triplet). Standard dashboard color pickers often struggle with the separate white channel or don't format the payload exactly as the KNX bus expects. To solve this, I built a custom Template node utilizing Vuetify, and I’m sharing the code so you can drop it straight into your own projects. The ETS 6 Setup Before diving into Node-RED, ensure your actuator (or DALI gateway) is properly configured in ETS 6. You want to use the combined 6-byte group object for RGBW. This allows us to send the red, green, blue, a...

[ TRY IT OUT HERE: https://marcdahl.dk/knx/ ] If you spend enough time working with KNX, you eventually find yourself staring at the ETS Bus Monitor, trying to decode telegrams. While ETS provides a great high-level view, it doesn't show you the raw electrical reality of the twisted-pair (TP) bus. The way KNX TP telegrams are explained to beginners To bridge this gap, I built the KNX TP Telegram Visualizer. It is a tool designed to take standard KNX inputs and generate the exact physical bitstream and timing parameters as they would appear on the wire. Here is a look under the hood at how the visualizer works and how it models the KNX TP1 standard. 1. Stripping Away cEMI: Logical vs. Physical One of the biggest hurdles in understanding KNX telegrams is the difference between cEMI (Common EMI) and raw TP formats. The ETS Bus Monitor displays telegrams in the cEMI format. This format adds a two-byte wrapper (Message Code and AddIL) at the beginning of the frame and splits the routin...