Earlier posted in this forum is an article from 'Digit' who has connected his Remeha Calenta heating boiler to his computer.
With a little help from him I designed an ethernet interface with galvanic isolation. I also made 2 scripts to read the values
from the Remeha into Homeseer. This interface is based on a Ethernet-serial module from Wiznet. (this is the WIZ105SR).
This Wiznet module act as a virtual comport (in my configuration it is set to COM5).
The script can be used with my designed ethernet interface, but can also be used with the original Remeha cable or with an
interface that you build yourself.
The first script 'remeha_createdevices.vb' will create housecode R1 to R22.
The second script 'remeha_read' will read the Remeha boiler values from COM5 (can be set to your own setting)
this second script must be called from a recurring event (in my setup I call this every 5 minutes).
Communication from the Remeha to Homeseer is also CRC16-checked. this is done in the script.
Attached is a ZIP-file with: schematic, script, photo's
The interface I build has also a switch on it. With this switch I can use the external input on the thermostat (Isense). This external input is connected to
my digital I/O board that I use for several purposes. (this I/O board is also connected to Homeseer)
I did not comment out the functions and methods used in the script, also this script must be fine-tuned. I am working on it.