Using Source Routing - Digi XBee Zigbee Mesh Kit User Manual

Large networks routing
4. As the route record traverses the many-to-one route, each node in the route appends its own 16-
bit address into the payload of the route record.
5. When the route record reaches the data collector, it contains the address of the sender and the
16-bit address of each hop in the route.
6. The data collector can store the routing information and retrieve it later to send a source routed
packet to the remote module.
Note Source routing allows a data collector to route responses back to each device, supplying a many-
to-one data request without additional route table entries.

Using source routing

To use source routing:
1. The data collector must work in API mode.
2. The collector must send periodic many-to-one route request (AR parameter value must be
different from 0xFF).
3. You need a microcontroller or a PC connected to the data collector to automatically capture and
store the routes to the rest of network nodes.
These routes are used when transmitting a message to a remote node.
Acquire source routes
Acquiring source routes requires the remote nodes to send a unicast to the data collector (device that
sends many-to-one route request broadcasts). There are several ways to force remotes to send route
record transmissions:
The data collector can issue a network discovery command (ND) to force all XBees to send a
n
network discovery response. Each network discovery response will be prefaced by a route
record.
Periodic IO sampling can be enabled on remotes to force them to send data at a regular rate.
n
Each IO sample would be prefaced by a route record.
If the node identifier (NI) of the remote XBee is known, the DN command can be issued with
n
the NI of the remote in the payload. The remote node with a matching NI would send a route
record and a DN response.
If the application on remote nodes periodically sends data to the data collector, each
n
transmission forces a route record to occur.
Store source routes
To store source routes for remote nodes:
1. Remote nodes must first send a unicast transmission to the central collector.
2. Upon receipt of a unicast, the XBee emits a Route Record Indicator (0xA1) frame through the serial
interface.
3. The information from the route record frame must be interpreted and stored by the application on
the microcontroller for later use.
Transmit data
To transmit data using source routing:
XBee® Zigbee® Mesh Kit
Source routing
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