RFXtrx433E, Node-RED, MQTT and Home Assistant

This post describes how I have setup an RFXtrx433E device with a Raspberry Pi to transform data from inexpensive 433 MHz motion- and climate-sensors into MQTT messages on my local network. With the data available as MQTT messages I can store the data in InfluxDB for viewing in Grafana, show the data in Home Assistant and route the data to cloud services.

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The Sensor433 library and Geeetech transmitters and receivers

As I use 433MHz transmitters for sending sensor data from many of my IoT-nodes, I have made a re-usable Arduino library for this purpose. The transmitted sensor data is picked up by one single receiver (an ESP8266 board) that converts the values to MQTT messages on my local network. In this post I will describe this library, my setup and also a set of new 433MHz transmitters and receivers that I have upgraded to.

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Home Assistant – integrating RESTful switches

I have started integrating my IoT-devices and services with the Home Assistant platform. See my previous post for details on getting started with Home Assistant and subscribing to MQTT messages:

Home Assistant – getting started and using MQTT sensors

My next attempt is to configure RESTful switches in HA for interacting with an existing web service that I use for controlling 433 MHz outlets. I will also add automation rules for the switches and test the voice command in Home Assistant.

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Preparing the remote control app for Christmas

Winter is soon to arrive in Sweden and the amount of daylight is decreasing every day. Thus it’s time to set up some extra light sources indoors and outdoors. I have been using my web app for remote controlled outlets (link) for some months now, but with the additional light sources needed for this time of year, I have to extend the application. As Sweden goes into the dark season I would also like to have an on/off schedule for some of the lights so that they are turned on/off automatically according to a set of specified events.

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Radio chirp data incorporated in an MQTT environment

Internet-of-things does not require that every device has to be directly connected to the Internet. The complexity and possible security issues with every sensor having its own IP address would in fact be overwhelming. A better approach would be to use more light-weight protocols for the sensor and actuator data and locally aggregate and filter these data at common points before making them available on the Internet. In this post I will describe a theory and implementation of transmitting small radio chirp messages from an Arduino Pro mini and then receive these data on a Raspberry Pi for transformation to MQTT messages for the Internet.

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A low energy open door detector with radio signals and MQTT

This blog post describes how I have set up a door-open detector at home. It uses a small ATtiny85 board that broadcasts a 433 MHz signal every time the door is opened. The signal is fetched by a Raspberry Pi that in turn publishes an MQTT message that results in the event being stored in a database and also being re-published to a cloud service. The circuit is only active when the door is open (and in that state only consumes 10mA), so the whole setup can be driven by a battery pack that is bound to last for a very long time.

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RCSwitch revisited – control RC outlets with a web app

In two previous posts, I used the RCSwitch and pi-switch libraries for communication between an Arduino Uno and a Raspberry Pi. I touched briefly on the main purpose with these libraries – to control RC outlets. In this post I will dig deeper and decode the RC signals so that the remote control can be replaced by a web app running on any browser-enabled device.

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