Communication via LAN to Raspberry

Hey together,

i’m going to plan my new home as a smart home. So I want to read the state of all Switches and taster, Control all sockets and so on. It is not possible to get all cables to a central Point, because it is an existing house. Using knx for every item would be to expensive.

So my plan till now would be, to connect every item to a central Point in its room. There would be a Raspberry Pi to Control those items. I’m at the beginning of my plan. So my question is, is it possible to communicate between OpenHab and the Raspberry via LAN?

Thanks a lot for helping answers.
Best Greetings,

@WilliamspiderWeb, just to answer your question: Of course you can communicate between an openHAB and a separate RPi. You can do this via several ways (check for bindings: MQTT, HTTP, Exec…)

But: If I got you right, you’re planning to wire switches and/or sockets somehow to the RPi (GPIO?) to do something like switching lights, sockets and so on.

Honestly, I’m not sure, if this will give you the usage experience you’re trying to achieve :wink:

If you can’t install cables for a bus system (e.g. KNX, LCN) you may consider RF-based solutions like Z-Wave.
Z-Wave has been proven to get a very tight and stable integration into openHAB. And many, many devices/plugs/switches/motion detectors etc. are available …

Thanks for your quick response.
You got me right. I would control the switches and sockets to the GPIOs of the RPi.

Using a bus system like KNX would be the nicer solution, because there is just one bus cable which has to be wired from one to the other. Installing the bus cables is not the problem. But you would pay about 30 EUR more for each socket. If there are 100 sockets in the house, it is just 3000 EUR additional just for sockets. So I think using KNX for the sockets would be the more expensive solution… If I’m wrong, just tell me. :slight_smile:

RF-based solutions are good for sensors and actors after fixing up the home if you’ve forgotten something. But if I have the choice I prefer cables.

So if I would communicate via MQTT or HTTP over the CAT7 cable with the RPi it is possible to see and use the socket (which is controlled by the RPi GPIO) on the Dashboard of OpenHAB.

The point is I have to plan the infrastructure now, but I will program/configure the smart home later. That’s why I can’t spend to much time in learning how OpenHAB works for now. But although I have to build up my infrastructure… That is not the easiest way. :wink:

Yes, exactly! So did I: Z-Wave and Zigbee where the bus (KNX in my case) isn’t possible or was forgotten :sunglasses:

If you want to have 100+ sockets switchable on KNX, you should consider 12-fold or 20-fold aktuators. But even using them, you’ll be at 15 to 20 EUR per switched channel. Yes, it remains costly but what you get for the money is well tested an very reliable. If you have done so, you’ll never regret - at least I did not :wink:

The latter is certainly true for other professional installation bus systems as well (with or without dedicated bus cables like LCN, DigitalStrom etc.). Although liking KNX personally, I’m not arguing for or against a specific system.

At the end, it just has to be rock solid and should work even without permanent support (at least for the basics) of its developer (YOU!) :wink:

I agree in all points… especially the last one. I’ll do my very best not to support my own system permanently. :wink:

Absolutely. And I do something similar. I use a python script I wrote called sensorReporter to do just that. I prefer MQTT but you should be able to use HTTP REST as well.

Thanks for your help. That seems to be exactly what I need. Then I will wire my home like I have planed it and come back to you later on when I will start programming and configuring.

May I ask you how you have realized the hardware at the Raspberries?

I’m not sure specifically what you are asking so I’ll do my best.

I have three Pis in my system thus far.

Purpose - Bluetooth device presence detection and RFM69 wireless gateway

First generation Pi B
Wired ethernet networking

Bluetooth Dongle for BT device presence detection
RFM69HW transceiver connected to GPIO

Purpose - Bluetooth device presence detection and door and window sensor reporting

First generation Pi B
Wifi dongle networking

Bluetooth dongle for device presence detection and reed switches directly wired to GPIO pins

Purpose - Garage door controllers and sensors, bluetooth device presence detection, reelyActive server, IP camera

Third generation Pi
Built in wifi networking

Built in Bluetooth dongle

Dual relay wired to GPIO pins and garage door opener buttons.
Reed switches wired to GPIO pins

I use sensorReporter to report Bluetooth device presence detection reporting, the software that bridges the RFM69HW wireless network to MQTT, to report changes in state on the reed sensors wired to the GPIO, and to command the relays wired to the GPIO.

I use a script I wrote for reelyActive to report its Bluetooth detections to MQTT. Search the forum for reelyActive for that code and updated examples.

I use ffmpeg to stream the IP camera.