XB24-BCIT-004 Digi International/Maxstream, XB24-BCIT-004 Datasheet - Page 18

• Manufacturer Part Number: XB24-BCIT-004
• Description: MODULE 802.15.4 SER 2 CHIP ANT
• Manufacturer: Digi International/Maxstream
• Series: XBee™r

Specifications of XB24-BCIT-004

• Frequency: 2.4GHz
• Data Rate - Maximum: 250kbps
• Modulation Or Protocol: 802.15.4
• Applications: Home/Building Automation, Industrial Control, ZigBee™
• Power - Output: 2 mW (3 dBm)
• Sensitivity: -96dBm
• Voltage - Supply: 2.1 V ~ 3.6 V
• Current - Receiving: 38mA
• Current - Transmitting: 35mA
• Data Interface: PCB, Through Hole
• Antenna Connector: On-Board, Chip
• Operating Temperature: -40°C ~ 85°C
• Package / Case: Module
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Memory Size: -

3. ZigBee Networks
3.1. ZigBee Network Formation
3.2. ZigBee PANs
3.2.1. Starting a PAN
Zigbee networks are called personal area networks (PAN). Each network contains a 16-bit
identifier called a PAN ID.
ZigBee defines three different device types – coordinator, router, and end device. An example of
such a network is shown below.
Figure 3‐01. Node Types / Sample of a Basic ZigBee Network Topology
Coordinator – Responsible for selecting the channel and PAN ID. The coordinator starts a new
PAN. Once it has started a PAN, the coordinator can allow routers and end devices to join the PAN.
The coordinator can transmit and receive RF data transmissions, and it can assist in routing data
through the mesh network. Coordinators are not intended to be battery-powered devices. Since
the coordinator must be able to allow joins and/or route data, it should be mains powered.
Router – A router must join a ZigBee PAN before it can operate. After joining a PAN, the router
can allow other routers and end devices to join the PAN. The router can also transmit and receive
RF data transmissions, and it can route data packets through the network. Since routers can allow
joins and participate in routing data, routers cannot sleep and should be mains powered.
End Device – An end device must join a ZigBee PAN, similar to a router. The end device,
however, cannot allow other devices to join the PAN, nor can it assist in routing data through the
network. An end device can transmit or receive RF data transmissions. End devices are intended
to be battery powered devices. Since the end device may sleep, the router or coordinator that
allows the end device to join must collect all data packets intended for the end device, and buffer
them until the end device wakes and is able to receive them. The router or coordinator that
allowed the end device to join and that manages RF data on behalf of the end device is known as
the end device’s parent. The end device is considered a child of its parent.
ZigBee networks are formed when a coordinator first selects a channel and PAN ID. After the
coordinator has started the PAN, routers and end devices may join the PAN. The PAN ID is selected
by the coordinator when it starts the PAN. Routers and end devices become a part of the PAN (and
inherit the coordinator’s PAN ID) when they join a PAN.
ZigBee supports mesh routing in the network, allowing data packets to traverse multiple nodes
(multiple "hops") in order to reach the destination node. This allows ZigBee nodes to be spread
out over a large region, and still support communications amongst all devices in the network.
All devices in a ZigBee network receive a 16-bit address (network address) when they join a PAN.
The 16-bit address of the coordinator is always 0.
Since the coordinator is responsible for starting a ZigBee network, all ZigBee networks must have
a coordinator present initially. To start a PAN, the coordinator performs a series of scans to
© 2008 Digi International, Inc.
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