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mcci-catena / arduino-lmic

LoraWAN-MAC-in-C library, adapted to run under the Arduino environment
https://forum.mcci.io/c/device-software/arduino-lmic/
MIT License
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NB_Rep - Strange behaviour #670

Closed Cloolalang closed 3 years ago

Cloolalang commented 3 years ago

mcci-catena/arduino-lmic 3.2.0 on TTGO v1 EU868, Rak Gateway with internal Loraserver.

I would like to be able to change/set/control NB_Rep ( the number of times uplink packets are transmitted (with the same frame number) as this is a redundancy feature for packet-loss control in the LoRaWan specification (amongst other parameter such as TX_Power and SF).

So I dug around in this library, and found in lmic.c, line 602:

LMIC.upRepeat = 0;

I found that if I change this I do start seeing repeating uplinks with same frame number, great it works!

BUT:

When I changed it back my TTGO still sends repeated uplinks!, oh no!! (ADR is set to OFF)

I did something to permanently set my node to send repeated uplinks and the only why I can stop that now is to set LMIC.upRepeat = 0; before every transmission (LMIC_setTxData2…)

Any Idea how I manged to do this, or how I can fix it?

Thanks very much for this great project, its been very useful to be able to tweek the LoraWan parameters

Cheers P

terrillmoore commented 3 years ago

Well, I'll spare you a long discussion; there's no proper API for using this. That's to say, it's only been tested when the network controls it, which means it only changes at moments when a message has been received (thereby setting LMIC.upRepeatCount to zero). I would experiment with resetting LMIC.upRepeatCount whenever you change LMIC.upRepeat. Other than that, no idea why you're getting repeated uplinks when LMIC.upRepeat is zero.

Best regards, --Terry

Cloolalang commented 3 years ago

Thanks Terry, I'll take a look an d let your know what I discover! I really appreciate your insights and all that you have done so far with LMIC Cheers Patrick