CD_LoRaBasicsModem_Demo

Connected Development sample LoRaWAN demo using Semtech LoRa Basics Modem.

Description

The application will automatically start a procedure to join a LoRaWAN network (see configuration).

Once a network is joined (i.e. when the corresponding event is triggered), uplinks are sent periodically. This periodic action is based on the LoRa Basics Modem alarm functionality. Each time the alarm-related event is triggered, the application requests an uplink.

The content of the uplink is the value read out from the charge counter by calling smtc_modem_get_charge().

The application is also capable of displaying data and meta-data of a received downlink.

Configuration

Several parameters can be updated in main_lorawan.h header file:

Constant	Description	Possible values	Default Value
LORAWAN_APP_PORT	LoRaWAN FPort used for the uplink messages	[1, 223]	2
LORAWAN_CONFIRMED_MSG_ON	Request a confirmation from the LNS that the uplink message has been received	{true,false}	false
APP_TX_DUTYCYCLE	Delay in second between two uplinks	uint32_t	60

LoRaWAN configuration

The LoRaWAN Join configuration is handled by the function apps_modem_common_configure_lorawan_params().

The join parameters (DevEUI, JoinEUI and AppKey) are taken from lorawan_key_config.h.

Constant	Description	Possible values	Default value	Note
LORAWAN_DEVICE_EUI	LoRaWAN device EUI	Any 8 bytes c-array	{0xFE, 0xFF, 0xFF, 0xFF, 0xFD, 0xFF, 0x00, 0x00}	Used if USER_DEFINED_JOIN_PARAMETERS is defined
LORAWAN_JOIN_EUI	LoRaWAN join EUI	Any 8 bytes c-array	{0x00, 0x16, 0xC0, 0x01, 0xFF, 0xFE, 0x00, 0x01}	Used if USER_DEFINED_JOIN_PARAMETERS is defined
LORAWAN_APP_KEY	LoRaWAN application key	Any 16 bytes c-array	{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}	Used if USER_DEFINED_JOIN_PARAMETERS is defined
LORAWAN_REGION	LoRaWAN region	Values in smtc_modem_region_t enumeration	SMTC_MODEM_REGION_EU_868	See supported LoRaWAN regions below
LORAWAN_CLASS	LoRaWAN class	Values in smtc_modem_class_t enumeration	SMTC_MODEM_CLASS_A	All LoRaWAN classes (A, B & C) are supported

The default build supports the US915 LoRaWAN region. Other regions can be selected by modifying the build.

LoRa Basics Modem event management

When LoRa Basics Modem is initialized, a callback is given as parameter to smtc_modem_init() so the application can be informed of events. In a final application, it is up to the user to implement this function.

In this demo application, this function is defined in apps_modem_event_process() implemented in apps_modem_event.c. Each example needs to implement the functions defined in apps_modem_event_callback_t that are useful to it - others have to be set to NULL.

Expected Behavior

Here follow the steps that shall be seen in logs to indicate the expected behavior of the application:

Device starts and reset

INFO: Modem Initialization
INFO: ###### ===== LoRa Basics Modem LoRaWAN Class A/C demo application ==== ######
INFO: ###### ===== BASICS MODEM RESET EVENT ==== ######

Following this print you shall find application and LoRaWAN parameters prints.

Device joined the network

INFO: ###### ===== JOINED EVENT ==== ######

Alarm event occured, generating uplink

INFO: ###### ===== ALARM EVENT ==== ######
INFO: Request uplink

Send done

INFO: ###### ===== TX DONE EVENT ==== ######