I just added a gateway and started testing LoraWan TTN few days ago. Everything is working fine, except by the downlinks.
I am testing on AU915 FS1 1.0.2, ABP and OTAA end devices, but I think I will use OTAA at the end.
The issue is the RX1Delay should be 5s, but looking to the timestamp at the gateway live data window, it looks like the downlink is executed imediately after the uplink. I think that is why my end devices are not receiving anything.
The strange thing is we can see by the log at the picture that TTN server is telling to the end device that RX1 delay is 5s, but it is not respecting this by itself.
Am I reading correctly this information? Am I missing anything?
That’s at most the time when the downlink request starts its journey back towards the gateway.
LoRaWAN transmissions are not timed using that sort of timestamp, but either with the 32 bit integer microsecond counter or the GPS time reported by the gateway itself. Also notice how the web log tick indicator is not even showing a 1 second difference there either - because not tracking the actual packet times.
If you are able to capture the full raw uplink and downlink reports, you’ll be able to see the time references actually used, and that they tell the gateway hardware to begin the transmission exactly to the microsecond 5 seconds after the end up the uplink.
It’s probably not the primary issue but your signal reports shows an overload-range RSSI indicating that your node is too close to your gateway. This is known to cause distortion and sometimes problems.
Yes, I have thought about that, but even with -65 rssi it does not work.
Actually I am not sure about the “acceptable” rssi level in this context, but -65 looks good to me.
I have noticed something strange in the module. When i ask it for the RX2 freq, by AT commands, it returns a strange number, like 96775. If I try to setup the frequency (which should be 923300000) it fails. The module does not support RX1 offset setup, at least by its technical guide.
I will try to setup factory defaults and configure it again.
Put another way, how close is your gateway & device? Getting the RSSI down (or up, depending on which way you look at it) is counter-intuitive-productive.
The consensus on here is that it’s 5m + brick wall.
Definitely not in the same room unless it’s a stadium. Or you have some 50Ω resistors.
Either way, it’s easy enough to test - move one or other a good few meters away and see what happens.
