Indeed, I was looking for a simpler and lower level protocol. Thanks for mentioning the network protocol anyway, because I have never heard of CoAP until now. It may come in handy in the future (or maybe for someone else reading the post).
Thank you for your suggestion. Is it really that easy to implement? So far the people I talked with irl told me otherwise, but I will look into it and judge myself whether I am up to the task.
Thank you for your suggestions. Rs-485 seems to be what I was looking for. CAN could also work, but is it reasonably implementable? So far everyone who I spoke with about CAN said that it is a rather complex protocol with a lots of finicky details and an extra long standard. Perhaps I have just talked to the wrong people. I will look into it more thoroughly, and thanks again.
Hmmm… It does tick a lot of the boxes, but the ethernet protocol is way too complex with all of its layers and not reasonably implementable on a low-power microcontroller. Also it requires separate hubs for connecting multiple devices together unlike i2c, which is daisy chainable.
This seems more than interesting. Will check it out in detail, since I haven’t heard about it until now. Thanks for the suggestion!