I’ve been investigating missed join requests from my WLR089U0 custom node, and have made an interesting discovery, which was also discussed in Feb 2019 in Microchip SAMR34 Joining Denied - #45 by mrpackethead .
Join requests are being sent outside of the defined sub band. All of the data messages are sent in the correct sub band however. I can replicate the issue on the WLR089 Xplained board as well.
Some details about the setup:
End Device example project
@mrpackethead I’m wondering if there was any resolution with Microchip?
I think there are also issues with the frequency selection in ABP mode as well, but I didn’t have the RTL-SDR when I was fighting those issues.
I’m attaching a screenshot of 1 successive join attempts within SDRsharp. There were other join attempts outside the range, some far enough away to only see the noise surrounding them.