6 - Class C: Continuously Listening for Downlinks
End devices in Class C mode listen for downlinks except when they are broadcasting Class A uplinks, or the Class A receive windows are open.
Class C mode is enabled by identifying the end device as a Class C capable device when you register it on the network server. The network server will then immediately send any downlinks it receives over a single gateway.
Introduction
End devices in Class C mode listen for downlinks except when they are broadcasting Class A uplinks, or the Class A receive windows are open.
Class C mode is enabled by identifying the end device as a Class C capable device when you register it on the network server. The network server will then immediately send any downlinks it receives over a single gateway.
Class C Mode
Devices implementing Class A are only able to receive messages from the network server directly after sending an uplink. Section Opening Receive Windows of the Sending Messages Book describes this in detail. Class A devices may switch over into Class B mode, described in the Class B Book, which allows the device to open additional receive windows during which messages can be received from the network server. For those use cases where immediate action is required, such as turning off the water in the event of a leak, end devices must operate in Class C mode. In Class C mode, the device can receive messages at any time, except during Class A uplink transmissions or when listening for Class A downlink messages. Class C mode consumes higher power than classes A and B, requiring the device to be constantly connected to a mains power source or have its battery changed frequently.
Class C mode can also be used to send firmware updates over the air (FUOTA) to one or more devices. You can read more about FUOTA in the TR002 v1.0.0 FUOTA Process Summary Technical Recommendation.