something is strange with socket blocking
I set up a similar to lora-mac-nano-gateway network with 1 gw and 1 node (both LoPy4 devices). Once I upgraded the node's firmware to v1.20.1, it cannot receive acks anymore. As far as I checked, something is going wrong with the blocking mode of the socket (initially set to false). Once I set it to True, the ack is received, but I don't want the socked blocked all the time.
@jcaron I said a similar to lora-mac-nano-gateway example. If it was too different, I'd post the code.
So I guess you don't need a crystal ball to see that this example here https://docs.pycom.io/tutorials/lora/lora-mac-nano-gateway/ is not working.
@delta unless you provide the relevant code you and the associated logs and errors on both sides, what you expect to happen, and what actually happens, it’s going to be quite difficult to help you. Some people here have crystal balls, but not all of us do :-)