Communications

An overview of supported microFLUX 4LPi communications protocols.

CAN bus is required for configuration of the unit. It can also optionally be used during operation to monitor telemetry from the unit and control the channel states.

Terminating the CAN properly ensures signal integrity during operation. It is recommended that each end of the CAN network be terminated - this usually means that termination is enabled on the unit farthest away from the flight computer.

The CAN termination resistor can be enabled on the microFLUX using the CAN Terminator Enable setting. See the Settings sections for further details.

microFLUX supports the DroneCAN protocol over CAN bus. Connection over DroneCAN allows for channel turn on/off, telemetry, configuration and firmware updating. microFLUX can be connected to Hargrave Configurator through DroneCAN for an improved configuration and firmware updating experience.

Outputs can be turned on and off during runtime using the DroneCAN hardpoint Command message 1070.Command.uavcan. The following command values are used:

The units support Dynamic Node Allocation (DNA) within the DroneCAN ecosystem, allowing quick connection to an existing network. The downside is that on any given power-up event, the unit may change the Node ID it is assigned while on the network. This makes it difficult to review data and may even result in units not connecting if DNA is not operating. If all devices are known on the network then it is recommended to force the node IDs to a known value. When DroneCAN Force NodeID is enabled the preferred Node ID is forced. This ensures a given unit will connect using only the given ID. However, duplication of IDs should be avoided. Forcing a Node ID can reduce the time taken for the unit to be on the DroneCAN network from start-up.

The preferred Node ID (and the Node ID that will be forced if force node ID is enabled) on microFLUX units is configured using the DroneCAN Preferred Node ID setting.

The IDs that are used in telemetry and hardpoint command messages can be configured individually for the input bus and output channels. This ID is used across the different types of DroneCAN telemetry messages. Each ID should be unique for all messages types in use for the entire DroneCAN network.

DroneCAN supports arming through the 1100 ArmingStatus Message. By default, this message is required to turn output channels on with DroneCAN hardpoint command messages. The unit must receive a DroneCAN arming packet with the "STATUS_FULLY_ARMED" status within the configured armed message timeout (5s default duration) to remain armed or driving. The unit will immediately disarm after receiving an arming packet with the "STATUS_DISARMED" status .