I’m looking to build a network of remote counting sensors which are driven by arduinos and connected by electrons. I currently use these counters in a localised situation using the arduino so I don’t really want to mess with that part, but now I’m wanting to have a number of them spread around the place, and their results being displayed on a single screen.
The idea being that each time a count event happens I’ll ask the node arduino to output via uart to the electron which will then publish this string. Am I thinking correctly that at the ‘central’ end, I can have a single electron subscribe to each one of my remote nodes, and then update the result on an oled? Or am I going to need a central electron for each node?
This seems like the perfect application for the new mesh networking models. Xenons would replace your Arduinos and connect wirelessly by mesh to the central Boron, which replaces the Electron. If the distance is greater than 10 meters or so, you can add some more Xenon repeaters to allow for greater distances. You can publish from the Xenon and it can run the code you currently have on the Arduino. This is exactly what the mesh was set up to handle.
the mesh models won’t work in this instance as the node locations are separated by too much distance and I don’t have the ability to place repeaters in between. Each one will need its own cloud connection.
Yes, that is correct. One Electron can subscribe to each of your nodes. You can take advantage of the fact that when you subscribe, the name is a prefix. So, if for instance, you subscribe to "node", each of your nodes can publish with the names, node1, node2, etc. (or some other more descriptive name, as long as they start with some common prefix). That way, your central Electron only needs to subscribe once.
BTW, why are you using the Arduinos at all? Why not have the the node Electrons handle the sensors themselves?
In all honesty, laziness and time constraints. I already have an arduino sketch which parses the RS485 string and calculates the checksum before feeding just the piece of data I want out to the UART.
I am not brilliant at understanding code, and working out the arduino sketch drove me to near insanity. If I can find some time I would like to try to implement it on the Electron, to get rid of unnecessary components. For prototype however I’ll leave it on the Arduino.