For TCP, you will need to know the IP address of your target device.
That comes in nn.nn.nn.nn form
But Modbus-TCP devices also have (at least one) slave address aka slave id aka slave number. It’s just a simple number between 1 - 250
For most TCP devices it’s just 1 though.
But you’re already past this point??
Bit confused because the doc you show us talks about serial settings, implying its a Modbus-RTU device probably ove RS485 serial wiring
The holding registers are the ones that you can write to from OH. .
I expect the ones you are interested in will be the room modes and setpoints.
How did you find this document and how did you know how to connect to the Modbus tcp.
I own a Wavin sentio and all I can find is what port I need to connect to if I want to use it.
no standard ip configuration and it is for sure not setup as dhcp from start.
Comment; a lot of Modbus-TCP devices just don’t do DHCP at all, by design.
Modbus-TCP is reliant on IP address, no mechanism for naming etc., so fixed manually assigned IP is the order of the day.
yes I know but then there will be a standard IP adresse to connect to in the manual.
but I have found now that this system got Modbus RTU because you have to setup the baud rate and etc in the setup screen. and TCP it is ip adresses and port numbers.
it was confusing because the Modbus port is a normal ethernet lan port.