XBP24-DMWIT-250 Digi International, XBP24-DMWIT-250 Datasheet - Page 17

• Manufacturer Part Number: XBP24-DMWIT-250
• Description: XBEE-PRO MESH 2.4 EXTENDED
• Manufacturer: Digi International
• Series: XBEE-PRO™r

Specifications of XBP24-DMWIT-250

• Frequency: 2.4GHz
• Data Rate - Maximum: 250kbps
• Modulation Or Protocol: ISM
• Applications: General Purpose
• Power - Output: 18dBm
• Sensitivity: -100dBm
• Voltage - Supply: 2.8 V ~ 3.4 V
• Current - Receiving: 55mA
• Current - Transmitting: 250mA
• Data Interface: PCB, Through Hole
• Antenna Connector: On-Board, Wire Whip
• Operating Temperature: -40°C ~ 85°C
• Package / Case: Module
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Memory Size: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: Q4542387

XBee/XBee‐PRO DigiMesh 2.4 RF Modules
Node Discovery
The node discovery command can be used to discover all Digi modules that have joined a network. Issuing the ND com-
mand sends a broadcast node discovery message throughout the network. All devices that receive the command will send
a response that includes the device’s addressing information, node identifier string (see NI command), and other relevant
information. This command is useful for generating a list of all module addresses in a network.
When a device receives the node discovery message, it waits a random time before sending its own response. The maxi-
mum time delay is set on the ND sender with the NT command. The ND originator includes its NT setting in the transmis-
sion to provide a delay window for all devices in the network. Large networks may need to increase NT to improve network
discovery reliability. The default NT value is 0x82 (13 seconds).
a loopback cluster ID (0x12) on the data endpoint (0xE8). Any data sent to this cluster ID on the data endpoint will
be transmitted back to the sender. This is shown in the figure below:
The configuration steps to send data to the loopback cluster ID depend on the AP setting:
AT Configuration (AP=0)
To send data to the loopback cluster ID on the data endpoint of a remote device, set the CI command value to 0x12.
The SE and DE commands should be set to 0xE8 (default value). The DH and DL commands should be set to the
address of the remote (0 for the coordinator, or the 64-bit address of the remote). After exiting command mode, any
received serial characters will be transmitted to the remote device, and returned to the sender.
API Configuration (AP=1 or AP=2)
Send an Explicit Addressing ZigBee Command API frame using 0x12 as the cluster ID and 0xE8 as the source and
destination endpoint. Data packets received by the remote will be echoed back to the sender.
It is possible to measure the received signal strength on a device using the DB command. DB returns the RSSI value
(measured in –dBm) of the last received packet. However, this number can be misleading. The DB value only indi-
cates the received signal strength of the last hop. If a transmission spans multiple hops, the DB value provides no
indication of the overall transmission path, or the quality of the worst link – it only indicates the quality of the last
link and should be used sparingly.
The DB value can be determined in hardware using the RSSI/PWM module pin (pin 6). If the RSSI PWM functionality
is enabled (P0 command), when the module receives data, the RSSI PWM is set to a value based on the RSSI of the
received packet. (Again, this value only indicates the quality of the last hop.) This pin could potentially be connected
to an LED to indicate if the link is stable or not.
RSSI Indicators
© 2010 Digi International, Inc.
17