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lnlp / LMIC-node

LMIC-node | One example to rule them all. LMIC-node is an example LoRaWAN application for a node that can be used with The Things Network. It demonstrates how to send uplink messages, how to receive downlink messages, how to implement a downlink command and it provides useful status information. With LMIC-node it is easy to get a working node quickly up and running. LMIC-node supports many popular (LoRa) development boards out of the box. It uses the Arduino framework, the LMIC LoRaWAN library and PlatformIO.
MIT License
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Persist OTAA session across reboots #33

Closed giannoug closed 2 years ago

giannoug commented 2 years ago

First of all thanks for the project, it is a really good starting point for those new to LoRaWAN :)

My current issue is that my device can't hear for join messages after booting. I'll have to move the device outside first and then move it to its normal position to start transmitting messages. I've used ABP while testing with The Things Network but now that I switched to Helium (which only supports OTAA) this a huge issue.

I've read that I can persist the "network session key" and "application session key" on RTC memory on my ESP32 (I believe this would be an issue with all the board this project supports) but I'm a bit lost on whether this is correct or a simpler solution exists. Any thoughts?

lnlp commented 2 years ago

Thanks.

Saving and restoring session keys is currently not supported / not included in LMIC-node. The goal of LMIC-node is to serve as a basic example that works out of the box cross-platform. Persisting state in non-volatile storage to survive power cycles, reboots or deep sleep is not supported by LMIC-node because this is microcontroller platform and hardware dependent and the LMIC library does currently not provide any generic support (functions/hooks for storing and restoring LMIC state) to help implement this.

My current issue is that my device can't hear for join messages after booting. I'll have to move the device outside first and then move it to its normal position to start transmitting messages.

Looks like you have an RF connection issue to solve here as the device shall be able to both transmit and receive. If you are unable to receive downlink messages, this does not only impact join accepts but also means that your device cannot receive essential MAC commands from the network server. For LoRaWAN, even for ABP the device still needs to be able to receive downlink messages. ABP is not a synonym for 'transmit-only' (although with TTN V2 many devices were implemented as such (transmit-only)).

Maybe the following fork of LMIC-node, for an ESP32 device used with Helium can provide you some help: LMIC-node_Sensor-for-Helium-Network

giannoug commented 2 years ago

Looks like you have an RF connection issue to solve here as the device shall be able to both transmit and receive. If you are unable to receive downlink messages, this does not only impact join accepts but also means that your device cannot receive essential MAC commands from the network server. For LoRaWAN, even for ABP the device still needs to be able to receive downlink messages. ABP is not a synonym for 'transmit-only' (although with TTN V2 many devices were implemented as such (transmit-only)).

Thanks for the clarification. I'm able to receive downlink messages but not in the place I'd like to install the device. Maybe I'll need to fix that issue with a better antenna(?) first and then look into saving and restoring session keys.

Maybe the following fork of LMIC-node, for an ESP32 device used with Helium can provide you some help: LMIC-node_Sensor-for-Helium-Network

I'll surely have a look for ideas 👀 Thanks!

lnlp commented 2 years ago

Maybe I'll need to fix that issue with a better antenna(?) first

I would try to fix that issue first. A different antenna could possibly help. You may search the TTN forum for antenna (related) advice. Success.