Olimpia Splendid Bi2 Modbus Controller

THIS IS WORK IN PROGRESS, PLEASE LET ME KNOW IF THINGS ARE NOT WORKING, BUT DO NOT BLAME ME FOR IT

Temporary, crappy HowTo:

1. Configure, compile and flash Software (see Software section)
2. Wire up the modbus converter (see Hardware section)
3. Connect the modbus devices
4. Put your Fan Coil into "Remote" Mode (check the manual, for me, I think, it was touching "-" and the fan "button" for 10s)
5. If needed, change the fan coil address
6. Register the fan coil address (see registering/unregistering)
7. Change Fancoil Settings over http://CONTROLLER_IP/set?on=1

Controlling the fan coil over HTTP

HTTP examples: /set?addr=1&ambient=22.9&setpoint=23.0&on=0&speed=MIN&swing=False&fanonly=False&mode=COOLING

HTTP params:

• addr: (0...31) modbus address of the fancoil
• ambient: (XX.X) temperature in deg C of the current room temperature
• setpoint: (XX.X) temperature in deg C of the desired setpoint
• on: (true/false) ...on/off
• speed (MIN/MAX/AUTO/NIGHT): speed of the ventilator
• swing: (true/false): turn on/off swinging
• fanonly: (true/false): only turn on fan, do not heat ore cool
• mode: (COOLING/HEATING): mode

SOFTWARE

How to compile the software:

1. Download and install Platform IO ( https://platformio.org/platformio-ide )
2. chdir into the software folder
3. Copy src/configuration.example.h to src/configuration.h
4. Change the WiFi name and password in configuration.h (double check; they are case sensitive)
5. run "pio run" (or compile/run using Visual Studio)

HARDWARE

I used a Wemos D1 Mini Lite (but any ESP8266 should work fine, and the code should be adaptable to an ESP32 with minimal effort) with a MAX 485 Module like https://www.amazon.de/ANGEEK-MAX485-Module-Converter-arduino/dp/B07X541M2T Check out the PCB design in the pcb folder.

Wire Connections

ESP	MAX485
5V	5V
GND	GND
GPIO2 / D4	RO
GPIO0 / D3	RE
GPIO4 / D2	DE
GPIO5 / D1	DI

ADDRESSING

By default, the fancoil uses address 0 You can change the address of the fancoil by http://CONTROLLER_IP/changeAddress?sourceAddress=X&targetAddress=Y NOTE: EVERY fancoil connected to the modbus using the source address will change its address. Make sure you are changing addresses one by one.

Registering / Unregistering

Address must be registered. You can register an address by opening http://CONTROLLER_IP/ in a browser, enter the address (int) at the "register address form" and hit submit You should unregister unused fancoils, because the controller will try to reach the address periodically unnecessarily otherwise.