It is no such thing. Find out what a digital communications protocol is. Or for a short simple taster re-read what I have wrote.The protocol is manipulating current in one direction and voltage in the other so wired.
From the OpenTherm web site:
Standards for heating controllers
OpenTherm is a multi point to point communication protocol for use in residential heating. Furthermore, OpenTherm requires a standard type of connection like in any modern installation practice, i.e. a 2-wire low voltage and polarity-free connection. In addition OpenTherm can also be used as a wireless protocol.
OpenTherm is a multi point to point communication protocol for use in residential heating. Furthermore, OpenTherm requires a standard type of connection like in any modern installation practice, i.e. a 2-wire low voltage and polarity-free connection. In addition OpenTherm can also be used as a wireless protocol.
I doubt if any of you will understand most of this. It even gives the bits breakdown of the protocol.
https://www.domoticaforum.eu/uploaded/Ard M/Opentherm Protocol v2-2.pdf
OT/+ The OpenTherm/plus protocol provides a digital communications system for data-exchange between two microprocessor-based devices.
3. Physical Layer describes the characteristics of the physical medium and the method for bit-level signalling.
4. OT/+ DataLink Layer describes the composition of OpenTherm/plus frames and allowable conversation formats.
5. OT/+ Application Layer defines data objects and the mechanisms for transfer of application data between the boiler and room controllers.
4. OT/+ DataLink Layer describes the composition of OpenTherm/plus frames and allowable conversation formats.
5. OT/+ Application Layer defines data objects and the mechanisms for transfer of application data between the boiler and room controllers.
It was based on OSI (Open System Intercommunication), which is an open protocol suite, which was being pushed heavily by governments as it was non-proprietary, for general computer to computer communication. If all conformed to OSI all equipment made by anyone in the world could talk to each other. It never took off, but parts of its layers are in many other protocols. OpenTherm has an applications layer, datalink layer, etc. The layers are software, written and burned into firmware. Every OpenTherm device must have a microprocessor to communicate.
I don't expect anyone on here to understand the deep level aspects of the protocol, as you have no need to know it. A protocol is a frame split into selections with each section containing information. Look at this:
https://en.wikipedia.org/wiki/Ethernet_frame#Preamble_and_start_frame_delimiter
The above shows an Ethernet frame. OpenTherm will have something like it.
OpenTherm is a microprocessor (computer) protocol specifically for heating/cooling systems. The sections of the OpenTherm frames may relate to temperature, which is master, which is slave, etc. Each device acknowledges receipt of a frame to the sender, so constant two-way communication.
The layers of the protocol (each layer has a specific function) translates raw bits into information and even giving a man-machine interface that is represented in symbols (numbers and words), for humans to easily understand. Insisting that computers represent the man-machine interface as symbols, not O or 1s, was Alan Turings greatest achievement. Hence the screen you are looking at right now to communicate with the computer you are currently operating.
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