OpenDTU

Background

This project was started from this discussion (Mikrocontroller.net). It was the goal to replace the original Hoymiles DTU (Telemetry Gateway) with their cloud access. With a lot of reverse engineering the Hoymiles protocol was decrypted and analyzed.

Features for end users

• Uses ESP32 mikrocontroller and NRF24L01+
• Multi-Inverter support
• MQTT support
• Nice and fancy WebApp with visualisation of current data
• Firmware upgrade using the web UI
• Default source supports up to 10 inverters
• Timezone support

Features for developers

• The mikrocontroller part

  • Build with Arduino PlatformIO Framework for the ESP32
  • Uses ESPAsyncWebserver and Async MQTT client

• The WebApp part

  • Build with Vue.js

Flashing and starting up

First configuration

• After the initial flashing of the mikrocontroller, a Access Point called "OpenDTU-*" is opened. The default password is "openDTU42".
• Use a webbrowser to open the address http://192.168.4.1
• Navigate to Settings --> Network Settings and enter your WiFi credentials
• Currently you have to look at your router to determine the IP of the newly connected device

Building

• Building the WebApp

  • The WebApp can be build using yarn

  $ yarn install
  $ yarn build
  

  • The updated output is placed in the 'data' directory

• Building the mikrocontroller firmware

  • Visual Studio Code with the PlatformIO Extension is required for building