Just need help with terminology of this layout

ME: Beginner skill level with OH2 and am vague with scope of terms. Definite Advanced skill level with electronic circuitry, possible advanced skill level with general purpose scripting/programming/sysadmin. I just need an orientation to get me from a state of confusion (due to the ambiguity of terms chosen by OpenHAB developers) to a working first example.

SYSTEM: Headless Ubuntu server accessed mostly from offsite via ssh. Automation is accomplished substantially using Arduino, so the server is mainly a means of status and command transmission between Arduino and off-site computer.

Given my system configuration, I need help clearing the ambiguities of terms specific to my system. (Multiple synonyms in the documentation sure would have helped, especially relating the terms to the synonyms that would be commonly used at the electronics circuitry level for thing, item, and channel) I use an Arduino as, among other things, an interface to read a DHT11 temperature sensor and thereby control my furnace. I use that same Arduino, since it has has pins like a RaspPi, to control SSRs, etc. I can read and control the mode and state of any Arduino pin with always-connected USB communications, which I do for controlling 120 vac devices.

Examples of current use and hoped-for OH2 enhancement:

SITUATION 1:To query room temperature, my server sends some text commands to the Arduino, then waits for a response, parses out the temperature, and outputs that temp to STDOUT (CLI right now). I would like the text commands sent to the Arduino in response to a [remote] user’s computer browser rendering any form of any type of thermostat image. I would also like the return text (number + scale type) from said Arduino to get rendered in the browser view so the user sees the current room temperature. The Arduino controls the furnace and A/C so it receives and returns its temperature settings and state of the furnace/fan and A/C outputs. In addition to returning information, the Arduino sends info of its own accord, mostly so the furnace on/off times can be logged by the server. I’d like the thermostat image in the user’s browser to show the state of the furnace, not only when the image is first rendered, but also updated as the Arduino sends the relative info back to server.

SITUATION 2: Server sends command to Arduino to turns on outlet to coffee maker on a crontab-run schedule. Same scenario for a porch light. I’d like a [remote] user to have an icon (or mouse clickable screen region by whatever name) whereby the outlets could be remote controlled and read. Logging info does get sent to server as well.

So, in my scenarios, i hope someone can simply tell an electronics technician such as myself what the thing, item, channel, etc.? I have the Exec binding installed, do I need the String binding installed as well?

I would think the answers are simple. That will get me over the confusion I have. I can do the programming from there. THANK YOU!

The documentation is a good starting point, and has everything that you need with regard to the terminology and basic concepts.

Thank you, Jason. I’m trying, but the learning curve is difficult due to
me having to interpret terms. I am mentally trying to develop
cross-references for “item”, “channel”, “thing”, etc. For example, as I
read the documentation, the term “item” seems to actually mean a selectable
functionality or something like that. It is just hard for me to get past
mental blocks of this nature.

Start with the concepts section of the user docs. It does a good job describing all of this.

Can you blame me for my confusion? A light bulb is called an Item in the Concepts Overview section2 of the user docs but is called a Thing in the Concepts Things section!!!

[UPDATE] - I’m considering that my Arduino could be thought of as a Bridge, the code-ware thermostat inside it is another Thing as is the humidistat. Maybe the thermostat is a Bridge also with the settings of it being Things. The relays and SSRs could be Channels and the physical furnace and humidifier could be Items. ??

[INITIAL MUSINGS] - I’m coming to understand that SITUATION 1 could be understood as having one thing - the Arduino - and many items - furnace, furnace fan, A/C, temperature sensor, humidifier [future]. That leaves me wondering if the actual readings (of set-point settings and current humidity/temperature) are also items?

Or should I understand that the Arduino needs to be nameless, faceless incognito with the things being the Arduino-resident code-ware humidistat and thermostat, and items are the settings and readings and relays?

Or maybe it doesn’t matter where I place the conceptual boundaries as long as the parts are in the correct order of placement? I could make a light bulb a Thing and it would have extraneous, unuseable functionalities vs. making it an Item when it would have more appropriate functionalities?

Like I say, I’m struggling through it…

SITUATION 2 should be a piece of cake once I learn from the first situation.

My research shows me that this issue goes back to Eclipse SmartHome which I assume means it is beyond the control of OpenHAB. I’ll close this thread and see if I can get help from Eclipse SmartHome.