3 - Receiving Messages
Messages sent from a network server to an end device are referred to as downlinks. These are sent to the end device via a single gateway. If there are multiple gateways near a device, the network server will select the most suitable gateway to broadcast from. This means the end device does not need to consider de-duping.
Devices operating in Class A mode only receive downlinks during the receive windows opened following an uplink, as described in the section Opening Receive Windows of the Sending Messages Book.
Devices that support Class B mode as well as Class A can receive additional downlinks in receive windows opened at fixed time slots. Read more about Class B mode in the Class B Book.
Devices that support Class C mode as well as Class A can receive additional downlinks at any time. Read more in the Class C: Continuously Listening for Downlinks book.
Todo
Fix link
In this book, you learn how to receive and handle downlink packets using the LoRaWAN® 1.0.4 specification.
Handling MAC Commands
End Device Status Request (DevStatusReq)
The network server uses the DevStatusReq command to request the battery status and signal-to-noise ratio (SNR) for this DevStatusReq command. The end device must respond with a DevStatusAns, as described in section End Device Status Answer of the Sending Messages Book. The DevStatusAns contains the SNR and indicates either that the end device is connected to an external power source, the current battery level, or that the battery level cannot be retrieved.
Learn more in Section 5.5, ‘End-Device Status’ (page 35) of the LoRaWAN Link Layer Specification v1.0.4.