1.. zephyr:code-sample:: lorawan-class-a
2   :name: LoRaWAN class A device
3   :relevant-api: lorawan_api
4
5   Join a LoRaWAN network and send a message periodically.
6
7Overview
8********
9
10A simple application to demonstrate the :ref:`LoRaWAN subsystem <lorawan_api>` of Zephyr.
11
12Building and Running
13********************
14
15This sample can be found under
16:zephyr_file:`samples/subsys/lorawan/class_a` in the Zephyr tree.
17
18Before building the sample, make sure to select the correct region in the
19``prj.conf`` file.
20
21The following commands build and flash the sample.
22
23.. zephyr-app-commands::
24   :zephyr-app: samples/subsys/lorawan/class_a
25   :board: nucleo_wl55jc
26   :goals: build flash
27   :compact:
28
29Important Notes for Multiple Runs
30*********************************
31
32By default, this example will only succeed the first time it is run. On subsequent join attempts, the LoRaWAN network server may reject the join request due to a hardcoded ``dev_nonce`` value. According to the LoRaWAN specification, ``dev_nonce`` must increment for every new connection attempt.
33
34To run this sample multiple times, choose one of the following options:
35
361. **Manually Increment ``dev_nonce``:**
37   Modify the sample code to increment ``join_cfg.otaa.dev_nonce`` before each connection attempt and ensure it is preserved across reboots.
38
392. **Built-in Zephyr Settings Implementation:**
40   Enable :kconfig:option:`CONFIG_LORAWAN_NVM_SETTINGS` in the Kconfig. This allows proper storage and reuse of configuration settings, including the ``dev_nonce``, across multiple runs.
41