XBee®/XBee‐PRO® ZB SMT RF Modules
1.
If the application on remote devices periodically sends data to the data collector, each
transmission will force a route record to occur.
2.
The data collector can issue a network discovery command (ND command) to force all XBee
devices to send a network discovery response. Each network discovery response will be prefaced by a route
record.
3.
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.)
4. If the NI string of the remote device is known, the DN command can be issued with the NI string of the
remote in the payload. The remote device with a matching NI string would send a route record and a DN
response.
Storing Source Routes
When a data collector receives a route record, it sends it out the serial port 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 11 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.
To send a source-routed packet to R3, the application must send a Create Source Route API frame (0x21)
to the XBee, with a destination of R3, and 2 hops (R1 and R2). If the 64- bit address of R3 is 0x0013A200
404a1234 and the 16-bit addresses of R1, R2, and R3 are:
Device 16-bit address
R1
R2
R3
0xAABB
0xCCDD
0xEEFF
Then the Create Source Route API frame would be:
7E 0012 21 00 0013A200 404A1234 EEFF 00 02 CCDD AABB 5C
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DCD [ DIGITAL CORE DESIGN ]
