Specifications
XBee®/XBee‐PRO®SERFModules
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Acquiring Source Routes
Acquiring source routes requires the remote device to send a unicast transmission to a data
collector (device that sends many-to-one route request broadcasts). There are several ways to
force remotes to send route record transmissions.
1. If the application on remote devices periodically sends data to the data collector, each
transmission will force a route record to occur.
2. Periodic IO sampling can be enabled on remotes to force them to send data at a regular rate.
Each IO sample would be prefaced by a route record. (See chapter 8 for details.)
Storing Source Routes
When a data collector receives a route record, it sends it out the UART as a Route Record Indicator
API frame (0xA1). To use source routing, the application should receive these frames and store
the source route information.
Sending a Source Routed Transmission
To send a source routed transmission, the application should send a Create Source Route API
frame (0x21) to the XBee to create a source route in its internal source route table. After sending
the Create Source Route API frame, the application can send data transmission or remote
command request frames as needed to the same destination, or any destination in the source
route. Once data must be sent to a new destination (a destination not included in the last source
route), the application should first send a new Create Source Route API frame. The XBee can
buffer one source route that includes up to 10 hops (excluding source and destination).
For example, suppose a network exists with a coordinator and 5 routers (R1, R2, R3, R4, R5) with
known source routes as shown below.