
Transmission, addressing, and routing
Transmission timeouts
XBee/XBee-PRO® S2C ZigBee® RF Module
97
[64-bit address] + [Request Type] + [Start Index]
This example sends a Network Address Request as a broadcast transmission to discover the 16-bit
address of the device with a 64-bit address of 0x0013A200 40401234. The request type and start
index are set to 0, and the transaction sequence number is set to 0x44.
API frame
7E 001F 11 01 00000000 0000FFFF FFFE 00 00 0000 0000 00 00 44 34124040 00A21300 00 00 33
Field composition
0x001F
length
0x11
Explicit transmit request
0x01
Frame ID (set to a non-zero value to enable the transmit status message,
or set to 0 to disable)
0x00000000 0000FFFF 64-bit address for a broadcast transmission
0xFFFE
Set to this value for a broadcast transmission
0x00
Source endpoint
0x00
Destination endpoint
0x0000
Cluster ID (Network Address Request)
0x0000
Profile ID (ZigBee Device Profile)
0x00
Broadcast radius
0x00
Tx Options
0x44
Transaction sequence number
0x34124040 00A21300
00 00
Required payload for Network Address Request command
0x33
Checksum (0xFF - SUM (all bytes after length))
Description
This API frame sends a broadcast ZDO Network Address Request to obtain the 16-bit address of a
device with a 64-bit address of 0x0013A200 40401234. We inserted the bytes for the 64-bit address in
little endian byte order. You must insert data for all multi-byte fields in the API payload of a ZDO
command in little endian byte order. You must set the
AO
command correctly on an API device to
enable the explicit API receive frames to receive the ZDO response.
Transmission timeouts
The ZigBee stack includes two kinds of transmission timeouts, depending on the nature of the
destination device. Destination devices such as routers with receivers always on use a unicast
timeout. The unicast timeout estimates a timeout based on the number of unicast hops the packet
should traverse to get data to the destination device. For transmissions destined for end devices, the
ZigBee stack uses an extended timeout that includes the unicast timeout (to route data to the end
device's parent), and it includes a timeout for the end device to finish sleeping, wake, and poll the
parent for data.