Accéder au contenu principal

Externalize the BLE devices decoding in a library - TheengsDecoder

 These last years OMG has grown leveraging different types of libraries for device decoding:

And many others for sensors, actuators, processing, mqtt...

I thank all the maintainers and contributors of these libraries, without them, OMG would not exist.

As you know OMG support also Bluetooth device decoding and control, we are not relying on a library for this, but rather on the OMG code.

This is mainly due to the history, with the first reading of a Mi Flora by an HM10 integrated in November 2017 and the ESP32 reading of this same sensor in January 2018. 
After BLE devices were added from time to time to reach a list of more than 25 devices compatible.

A lot of other open-source software are using the BLE data broadcasted to propose a similar approach, sometimes dedicated to one or a range of devices, for a particular platform, or for a particular controller.
My opinion is that each time, a part of the wheel is reinvented, decoding data, converting hex to decimal, processing, defining sensors parameters... 
So why not have one library that does this, and can be used by different projects, platforms, or controllers. Leveraging one format for better interoperability.

This is how TheengsDecoder library was created.


With the great help of @h2zero we created and published this piece of code that converts a gibberish information into a human and machine readable format.

This library can decode data coming from various BLE broadcaster devices and provide a comprehensive json for each message. It can be easily extended thanks to an understandable decoder definition in json format also:

{
   "brand":"ThermoBeacon",
   "model":"WS02",
   "model_id":"WS02",
   "condition":["manufacturerdata", "contain", "100000001a11"],
   "properties":{
      "tempc":{
         "decoder":["value_from_hex_data", "manufacturerdata", 24, 4, true],
         "post_proc":["/", 16]
      },
      "hum":{
         "decoder":["value_from_hex_data", "manufacturerdata", 28, 4, true],
         "post_proc":["/", 16]
      },
      "volt":{
         "decoder":["value_from_hex_data", "manufacturerdata", 20, 4, true],
         "post_proc":["/", 1000]
      }
   }

I like the library approach because it enables other projects to benefit from the work and avoid finding everywhere in the open-source world duplicate functions with the same goals. 
Some other projects prefer to internalize the code by integrating these libraries, there are Pros and Cons but in the case of OMG, I prefer to take the other approach and propose these functionalities outside of OpenMQTTGateway.

I think that having this approach will avoid some wasted effort globally and enable other projects to have easy access to the decoding functions.

TheengsDecoder will be integrated into OpenMQTTGateway from version v0.9.9


Commentaires

Posts les plus consultés de ce blog

OpenMQTTGateway now reads Xiaomi Mijia Temperature and Humidity sensor

In the path of integrating BLE devices to OpenMQTTGateway I have found the Xiaomi Mi Jia Humidity and temperature sensor to be a good candidate. This little indoor sensor is able to measure temperature and humidity and to transmit these data by bluetooth low energy to your smartphone. As we already integrated another BLE device ( Mi Flora)  why not extending the integration scope of OpenMQTTGateway to this one. I ordered one to see if I was able to extract data from it. After a few weeks, I received it, a first test with nRF connect application showed me that this device diffuses data in a quite similar way compared to Mi Flora (using BLE service data exposition). From this point I had to determine the differences between the data sent from mi flora and the data sent from mi jia hum & temp sensor. The reverse engineering was similar to the one done with Mi Flora and with some offset implementation in the program I was able to read easily the humidity and temper...

433toMQTTto433 - Bidirectional ESP8266 NodeMCU gateway between RF 433Mhz signal and MQTT

The goal  is to act as a gateway between 433Mhz sensors and a MQTT broker or between the MQTT broker and 433Mhz actuators, It enables to: receive MQTT data from a topic and send RF 433Mhz signal corresponding to the received MQTT data  publish MQTT data to a different topic related to received 433Mhz signal  It can be an interesting part in an home automation system so as to interface sensors and actuators (wall sockets) with software like openhab . List of compatible sensors here The interest of putting this gateway to an ESP8266 and not on a raspberry pi is to be able to manage security actions at gateway level (power on a siren, cut power to certain devices) following RF data received by sensors without being dependent to the PI for security related actions. [EDIT] all infos are now centralized into  the github repository  take a look at it you will find up to date info about OpenMQTTGateway You need: Software: Mosquitto Arduino IDE latest versio...

Get your BLE sensors data into Home Assistant in 5 minutes

You can now upload your board directly from the web browser!  So let's imagine you want to read data from a sensor like a Mi Flora, an LYWSD03MMC, a weight scale, or any other BLE sensor from this list  Plug an ESP32 dev board to your computer USB port Go to this website: https://docs.openmqttgateway.com/upload/web-install.html Select esp32dev-ble Click the install button Depending on your board you may have to press the BOOT button Choose the port that the ESP is connected to. Wait until the process is complete. Release the BOOT button That's it, OMG is now loaded into your ESP32 board without Arduino IDE, platformIO or a binary flasher. Here are the steps in images: Now comes the Home Assistant part: Add the MQTT integration and activate auto discovery Create a user and a password (Configuration->Users) without administrator right for the gateway Well, this is enough for Home Assistant. So let's now connect both: Check the Wifi Access points available with your smartph...