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STM32W108 SimpleMAC demonstration applications
Table 11.
Command
i
f
j
20/54
Detailed command description
Display status information displays the status of the node including information
such as:
– Network role
– Radio on/off state
– In or out of a network
– Channel
– Power
– EUI64
– PAN ID
– Node ID
– Send rate
– Poll rate
Form a network can only be executed while not already in a network. To form the
network, the node first initializes all persistent states then loops over all channels
searching for the channel with the lowest energy. The node dwells on each channel
taking multiple energy readings and records the highest energy level seen on every
channel. After obtaining a maximum energy reading for each channel, the node
selects the channel with the lowest maximum energy reading and configures itself
for that channel. The node then assigns itself a random PAN ID and assigns itself
the short address (node ID) 0x0000.
Join a network can only be executed while not already in a network. To join the
network, the node first initializes all persistent states then loops over all channels
searching for a channel with a sun. On each channel, the node transmits a sun
search broadcast packet and then waits for 200 ms for a sun available response.
If the node does not receive a sun available broadcast response after 200 ms, it
moves on to the next channel. If the node never receives a sun available response
or cannot complete the join process on any channel, the node indicates this fact to
the user and the user must invoke the join network command to try again.
The sun only sends the sun available response if there is room in the sun's planet
table. If the node does receive a sun available response, the response includes the
sun's PAN ID as the source PAN ID. If the node receives more than one sun
available response, the node tries to join the first response it receives.
Multiple suns on the same PAN ID are not valid, and there is no collision detection
for this situation. The planet sends a join request unicast packet using long
addressing and the sun's PAN ID. When the sun receives the join request, the sun
attempts to place to the planet in its planet table. The planet table is a fixed size. If
there is no room in the planet table, the sun responds with a join denied unicast
packet. If there is room in the planet table, the sun allocates a new short ID to the
planet, puts the planet in its planet table, and responds with a join accepted unicast
packet. There is no error detection if the join process fails before the join accepted
or denied packet has been received.
The sun does not remove planets from its planet table unless the planet specifically
sends a leaving network packet.
Doc ID 16995 Rev 10
Description
UM0893
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