Hardware options
There are currently two possible hardware options for this project, both in need of external power supply. A self powered board is under development by a member of the community and is currently being tested.
Hardware v1 by @roarfred
Composed from a ESP12E (or F) chip, this ESP8266 based board is designed specifically for this project with an on board M-bus chip.
Building this project will require some skills in ordering and assembling electronic circuits as well as programming. No detailed instructions are available.
The completed board mounted in a 3D printed enclosure
Assembly of readily available modules
You can also use a ESP based development board and combine this with a M-Bus module. Here are a few boards that have been tested, each one has a dedicated firmware file in the releases section.
ESP8266 based boards
- M-Bus connected to GPIO5 (D1)
- Jump GPIO4 (D2) to GND to force AP mode during boot
- Dallas temp sensor connected to GPIO14 (D5)
ESP32 based boards
- M-Bus connected to GPIO16
- Jump GPIO4 to GND to force AP mode during boot
- Dallas temp sensor connected to GPIO14
- M-Bus connected to GPIO16
Combine one of above board with an M-Bus module. Connect 3.3v and GND together between the boards and connect the TX pin from the M-Bus board to the dedicated M-Bus pin on the ESP board.
