XBP09-DMDK Digi International, XBP09-DMDK Datasheet - Page 15

• Manufacturer Part Number: XBP09-DMDK
• Description: KIT STARTER PROMESH XBEE PRO
• Manufacturer: Digi International
• Series: XBEE-PRO™r
• Type: Transceiver, XBeePror

Specifications of XBP09-DMDK

• Frequency: 900MHz
• Wireless Frequency: 900 MHz
• Interface Type: RS-232, USB, UART
• Modulation: FHSS
• Security: 128 bit AES
• Operating Voltage: 3.3 V
• Output Power: 50 mW
• Antenna: RPSMA
• For Use With/related Products: Xbee-PRO Modules
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 602-1130

3. XBee‐PRO® DigiMesh 900
DigiMesh Networking
DigiMesh Feature Set
Data Transmission and Routing
Unicast Addressing
Broadcast Addressing
Mesh networking allows messages to be routed through several different nodes to a final
destination. DigiMesh firmware allows OEMs and system integrators to bolster their networks with
the self-healing attributes of mesh networking. In the event that one RF connection between
nodes is lost (due to power-loss, environmental obstructions, etc.) critical data can still reach its
destination due to the mesh networking capabilities embedded inside the modules.
DigiMesh contains the following features
When transmitting while using Unicast communications, reliable delivery of data is accomplished
using retries and acknowledgements. The number of retries is determined by the NR (Network
Retries) parameter. RF data packets are sent up to NR + 1 times and ACKs (acknowledgements)
are transmitted by the receiving node upon receipt. If a network ACK is not received within the
time it would take for a packet to traverse the network twice, a retransmission occurs.
To send Unicast messages, set the DH and DL on the transmitting module to match the
corresponding SH and SL parameter values on the receiving module.
Broadcast transmissions will be received and repeated by all nodes in the network. Because ACKs
are not used the originating node will send the broadcast four times. Essentially the extra
transmissions become automatic retries without acknowledgments. This will result in all nodes
repeating the transmission four times as well. In order to avoid RF packet collisions, a random
delay is inserted before each node relays the broadcast message. (See NN parameter for details
on changing this random delay time.) Sending frequent broadcast transmissions can quickly
reduce the available network bandwidth and as such should be used sparingly.
The broadcast address is a 64 bit address with the lowest 16 bits set to 1. The upper bits are set
to 0. To send a broadcast transmission set DH to 0 and DL to 0xFFFF. In API mode the destination
address would be set to 0x000000000000FFFF.
© 2008 Digi International, Inc.
• Self-healing
• Peer-to-peer architecture
• Quiet Protocol
• Route Discovery
• Selective acknowledgements
• Reliable delivery
• Sleep Modes
Any node may enter or leave the network at any time without causing the network as a whole
to fail.
No hierarchy and no parent-child relationships are needed.
Routing overhead will be reduced by using a reactive protocol similar to AODV.
Rather than maintaining a network map, routes will be discovered and created only when
needed.
Only the destination node will reply to route requests.
Reliable delivery of data is accomplished by means of acknowledgements.
Low power sleep modes with synchronized wake are supported, with variable sleep and wake
times.
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