Atmel AVR2070 Network Router User Manual


 
42
AVR2070
8240B-AVR-06/09
Table A-6-3. End node E2 to Coordinator C via Router R2
E2 FCF
Data
0x8861
Seq
34
PID
0x1234
R2 SA
0x0006
E2 SA
0x0007
Final Dest
SA
0x0000
Origin SA
0x0007
Data
payload
A data frame from a child node is passed to the coordinator. The source and
destination addresses in the 802.15.4 frame header are changed for each hop, but
the rest of the frame is unchanged. Final destination and origin addresses do not
change as the packet progresses through the network.
A data frame may pass through the coordinator, if the “Dest SA” field is anything but
0x0000 (coordinator's short address). Any frame the coordinator sends, whether it is
relayed through the coordinator or originates with the coordinator, is preceded by a
routing packet if necessary.
A.7 Packet Formats
There are only a few packets used in this system, so structures can be pre-defined for
each. The key values used to distinguish one frame type from another are the FCF
value and the MAC Command byte.
Note that a new MAC command byte of 0xBB has been defined for a routing packet.
This is of course non-standard; however, it is not expected that other proprietary
networks are able to route RUM packets, so nodes in another network should never
have to parse a RUM routing packet.
Table A-7-1. Pre-defined packet types
Type FCF MAC CMD
Beacon request 0x0803 7
Beacon 0x8000 -
Association Request- direct 0xC863 1
Association Request- indirect 0x8863 1
Association Response – indirect 0x8863 2
Association Response – direct 0x8C63 2
Routing packet 0x8863 0xBB
Data packet 0x8861 -