Hello,
It seems that the rx2_dr option from the toml region definition file is ignored for the join sequence, do you confirm this ?
I think that the specification for EU868 for instance says that DR0 is the default RX2 datarate, but I’m not sure that it forbids to use something else, right ?
I was trying to test RX2 window using an LLCC68 radio chip which only supports SF7-SF9 at 125khz, but when I set rx2_dr to 3, the gateway still gets a downlink request at SF12 from chirpstack LNS.
How would a device know the Rx2 datarate when it hasn’t gotten any information from the server yet?
The JoinAccept is like a goodie-bag: once you’ve arrived, you know what’s in there. But before you got there, you don’t know what’s going to happen so it’s all default.
Depending on the stack you use, you may be able to configure the Rx2 datarate before the device has joined. (I guess you’re trying RadioLib, which does support this.)
Hello,
Yes, I’m aware that this configuration would be an “out of band” configuration.
For example, for some reason, a private network doesn’t want to use SF12, never, because the devices use an LLCC68 radio which doesn’t support this spreading factor.
Of course, the end-device should be configured accordingly to configure its RX2 window with the same datarate as the network server configuration.
But I don’t think that this is forbidden by LoRaWAN specification, right ?
As long as both the end-device and the network server are aware of the same settings, then it is all good. If it were forbidden, the option wouldn’t be there
But the point of my question here is that, in chirpstack LNS, there is a rx2_dr configuration option which seems to be taken into account only after join.
So the question to the Chirpstack developpers was, could it be possible that it is also taken into account for join accept.
