Set RX2 parameters
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I'm working with a network where RX2 is set to SF9, not the default SF12. Is there any way for LoPy to use different settings for RX2? (Is it simply a matter of adding a channel with updated settings? If so, which channel for EU868?)
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@prashanth I have seen that TTN uses SF9 @ 869.525 MHz for the RX2 response. There is a rational that a gateways can send with higher power at that frequency, and therefore cover the same distance, while having shorter transmission times. That works, if the node has been connected with OTAA. In that case the RX2 parameters are sent to the node.
I was a little bit surprised when I stumbled over that.
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Hey, have you found a solution for this?
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@kersing
My interpretation of "default" means until/unless a different parameter has been selected via the DLsettings mechanism.One major goal of LoRaWAN and the LoRa Alliance is to guarantee interoperability so (public) networks and certified devices shouldn't really be using different core settings that break that interoperability.
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@jmarcelino said in Set RX2 parameters:
That sounds like a bug on the network server side and deviation from the LoRaWAN standard
In this case it is an choice of the network operator for their development network. Checking the LoRaWAN specification (regional parameters document) it states: "The default parameters are 869.525 MHz / DR0 (SF12, 125 kHz)".
I'm not sure whether "default" implies mandatory. If not the operator is free to choose other settings...
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@jmarcelino Actually as LoPy is a development board we would like to have under control all parameters and RX window is the one which is mostly customized by guys who want to play with LoRa. I'm currently trying to get downlink data in Lopy and as no examples worked for me wanted to try different options with RX windows.
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@kersing
That sounds like a bug on the network server side and deviation from the LoRaWAN standard... and I remember someone with your name posting a fix for it ;-)https://github.com/kersing/ttn/commit/915bb5e22dd1e78859b35f00b16edcf528cfec58
If you can't fix the network server the only workaround I know is to force it on the C code, as it's also done for Semtech's own broken server
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@jmarcelino Yes it does. However the response is send in RX2 at SF9 so the LoPy is not able to receive it and adapt the parameters of the stack.
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Does this mistery network send the correct RX2 data rate in the DLsettings section of the OTAA join accept response?
If so I believe the LoPy will pick it up automatically.
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No. For the time being I've put my pycom devices to the side. I'm using other LoRaWAN devices where questions about basic usage are answered...
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@kersing I'm also interested in this. Have you found a solution?