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Appendices
B.2.4 Data-to-Service Frame
A Data-to-Service frame is used to send data to a specific service on a remote node,
for which the IEEE/MAC address is known. Both the source address and destination
address are included in the frame (the source address is in the header).
The Data-to-Service frame structure is shown below.
Header
(12 bytes)
Destination Address
(8 bytes)
Src Service
(4 bytes)
Data
(Max: 75 bytes)
Dst Service
(4 bytes)
Figure 8: Data-to-Service Frame Structure
If the Response-Required flag is set in the Frame Type field (in the header), the
remote node sends a response back to the local node. The response frame is identical
to the request frame except that the Response-Required flag is cleared and the
Response flag is set.
B.2.5 Establish-Route Frame
The Establish-Route frame is sent by a device to establish a route from itself all the
way up the branch that it has joined, ending at the Co-ordinator. Routing table entries
are created in all ascendant nodes, with the sole exception of the node's parent.
The frame is initially passed to the node's parent. It is then passed upwards to the next
node in the tree, which adds a Routing table entry for the local node, before passing
the frame up the branch. Each time a Routing table entry is created, the next hop
address is the address of the node from which the frame has been received.
The Establish-Route frame structure is shown below.
Header
(12 bytes)
Node Depth in Network
(2 bytes)
Number of Descendants
(2 bytes)
Figure 9: Establish-Route Frame Structure
The source address of the local node is included in the frame (in the header), along
with the number of descendant nodes (including immediate children) of which the
node is aware. If the Response-Required flag is set in the Frame Type field, the Coordinator node sends a response back to the local node. The response frame is
identical to the request frame except:
ƒ the Depth field is set to the depth of the local node in the network
ƒ the sequence number is not the same
ƒ the Response-Required flag is cleared
ƒ the Response flag is set
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© NXP Laboratories UK 2010
JN-UG-3041 v2.0