Hello Tilman, this is really a very nice design. I have ordered a pack of PCBs from elecrow, based on your gerber files, and have a few questions:
in your BOM you have listed 5 smd-capacitors and 7 smd resistors, but on the PCB i have solderpads for 6 capacitors and 8 resistors. Can you just explain?
is there a uniflächentaster-model for 2 ways?
i think i have to flash the bootloader first, do you have a tutorial for this, and a sample-sketch for the board?
Thank you very much
@TheoL Not only did I put in delays, too, but I put in delays that were based upon the ID (which was stored in NVRAM)! This helped.
caveat: This is probably not accurate be helps to explain the challenges with a large network.
My initial experience with Arduino/nRF24 was using the libraries from TMRh20. Those libraries allowed a node to be a repeater, but only for 6 nodes. The primary node 0, master, only allowed 6 nodes to connect to it. The nodes connected to it also allowed 6 nodes. Subsequent nodes had to go through one of these repeating nodes. But the depth was only 4 deep. The master assigned node IDs if the node didn't already have one; similar to a MAC address.
The master also kept track of the addresses (ARP table?). Addresses were 4 octets (base in the form of D/C/B/A. A node connected directly to the master had an address of 0/0/0/a (where 0/0/0/0 was reserved for the master). A node connected through another node had an address of 0/0/b/a, and so forth.
But what happens is that a parent node has to mange the data from all its child nodes and their child nodes and their child nodes. Thus a node would get so bogged down dealing with this traffic that it din't do its sensor task very well.
It is my belief that MySensors either uses TMRh20's libraries or has developed some aspects based on his initial work. I see that that TMRh20 has a version 2 and I have not experimented with it. I did find that MySensors worked better than version 1.
Thus, my curiosity.
I am also duly impressed at the magnitude of hardware. Currently a nano like device from Aliexperss is US$2-3, nRF24 ~ US$1, power supply ~ US$1.50, power cord ?, case?, sensors!? While the hardware cost is daunting, even with a PCB it's a lot of work building those up. So, yeah, I'm impressed!
-OSD
