Battery-powered sensor devices work in such a way that they spend most of the time in a low-power (sleep) state and periodically (e.g. once per minute) they wake up, then they beam values from all sensors (in the same order as they are enumerated) and then they continue to sleep. Beaming values means that the device sends a packet with its payload filled in the same way as data received from Read Sensors with Types, except the values are in FRC format. The FRC values are received by aggregating repeaters and later made available for FRC. Please see example.
The packet has the following properties:
• setRFmode( _TX_STD );
• NonroutedRfTxDpaPacket = TRUE;
• _NADR = BROADCAST_ADDRESS;
• _NADRhigh = 0;
• _PNUM = PNUM_STD_SENSORS;
• _PCMD = PCMD_STD_SENSORS_READ_TYPES_AND_FRC_VALUES | RESPONSE_FLAG;
• _HWPID = <device HWPID>;
•
DpaApiRfTxDpaPacket(
Async, 0 );
Async is typically 0. When used with a value of 1, beaming is asynchronous and
when received by an aggregating coordinator, it is immediately passed to its
interface. Asynchronous beaming is only used for emergency values (e.g. a flood
has been detected).