Networking Addressing
Digi XBee3® 802.15.4 RF Module User Guide
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Addressing
Every RF data packet sent over-the-air contains a Source Address and Destination Address field in its
header. The XBee3 802.15.4 RF Module conforms to the 802.15.4 specification and supports both short
16-bit addresses and long 64-bit addresses. A unique 64-bit IEEE source address is assigned at the
factory and can be read with the SL (Serial Number Low) and SH (Serial Number High) commands. A
device uses its unique 64-bit address as its Source Address if its MY (16-bit Source Address) value is
0xFFFF or 0xFFFE. Since the default value for MY is 0, devices use short source addressing by default.
Send packets to a specific device in Transparent APImode
To send a packet to a specific device using 64-bit addressing:
n Set the Destination Address (DL + DH) of the sender to match the Source Address (SL + SH) of
the intended destination device.
To send a packet to a specific device using 16-bit addressing:
1. Set the DL parameter to equal the MY parameter of the intended destination device.
2. Set the DH parameter to 0.
Addressing modes
802.15.4 frames have a source address, a destination address, and a destination PAN ID in the over-
the-air (OTA) frame. The source and destination addresses may be either long or short and the
destination address may be either a unicast or a broadcast. The destination PAN ID is short and it may
also be the broadcast PAN ID (ID is set to 0xFFFF).
In Transparent mode, the destination address is set by the DH and DL parameters, but, in API mode, it
is set by the type of TX request used:TX Request: 64-bit address frame - 0x00 or TX Request: 16-bit
address - 0x01 frames. In either Transparent mode or API mode, the destination PAN ID is set with the
ID parameter, and the source address is set with the MY parameter if MY is less than 0xFFFE,
otherwise the source address is set with the device's serial number (SH and SL).
Broadcasts and unicasts
Broadcasts are identified by the 16-bit short address of 0xFFFF. Any other destination address is
considered a unicast and is a candidate for acknowledgments, if enabled.
Broadcast PAN ID
The Broadcast PAN ID is also 0xFFFF. Its effect is to traverse all PANs in the vicinity of a local device.
Short and long addresses
A short address is 16 bits and a long address is 64 bits. The short address is set with the MY
parameter. If the short address is 0xFFFE, then the address of the device is long and it is the serial
number of the device as read by the SH and SL parameters.
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