XB24-AWI-001 Digi International/Maxstream, XB24-AWI-001 Datasheet - Page 12

• Manufacturer Part Number: XB24-AWI-001
• Description: MODULE 802.15.4 1MW W/WIRE ANT
• Manufacturer: Digi International/Maxstream
• Series: XBee™r

Specifications of XB24-AWI-001

• Frequency: 2.4GHz
• Data Rate - Maximum: 250kbps
• Modulation Or Protocol: 802.15.4
• Applications: Home/Building Automation, Industrial Control, ZigBee™
• Power - Output: 0dBm
• Sensitivity: -92dBm
• Voltage - Supply: 2.8 V ~ 3.4 V
• Current - Receiving: 50mA
• Current - Transmitting: 45mA
• Data Interface: PCB, Through Hole
• Antenna Connector: On-Board, Wire Antenna
• Operating Temperature: -40°C ~ 85°C
• Package / Case: Module
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Memory Size: -

XBee®/XBee‐PRO® RF Modules ‐ 802.15.4 ‐ v1.xEx [2009.09.23]
Flow Control
DI (Data In) Buffer
DO (Data Out) Buffer
Figure 2‐03. Internal Data Flow Diagram
When serial data enters the RF module through the DI pin (pin 3), the data is stored in the DI Buf-
fer until it can be processed.
Hardware Flow Control (CTS). When the DI buffer is 17 bytes away from being full; by default,
the module de-asserts CTS (high) to signal to the host device to stop sending data [refer to D7
(DIO7 Configuration) parameter]. CTS is re-asserted after the DI Buffer has 34 bytes of memory
available.
How to eliminate the need for flow control:
Case in which the DI Buffer may become full and possibly overflow:
Refer to the RO (Packetization Timeout), BD (Interface Data Rate) and D7 (DIO7 Configuration) com-
mand descriptions for more information.
When RF data is received, the data enters the DO buffer and is sent out the serial port to a host
device. Once the DO Buffer reaches capacity, any additional incoming RF data is lost.
Hardware Flow Control (RTS). If RTS is enabled for flow control (D6 (DIO6 Configuration)
Parameter = 1), data will not be sent out the DO Buffer as long as RTS (pin 16) is de-asserted.
Two cases in which the DO Buffer may become full and possibly overflow:
Refer to the D6 (DIO6 Configuration) command description for more information.
1.
2.
If the module is receiving a continuous stream of RF data, any serial data that arrives on the DI
pin is placed in the DI Buffer. The data in the DI buffer will be transmitted over-the-air when the
module is no longer receiving RF data in the network.
1.
2.
© 2009 Digi Internatonal, Inc.
Send messages that are smaller than the DI buffer size (202 bytes).
Interface at a lower baud rate [BD (Interface Data Rate) parameter] than the throughput
data rate.
receive data from the transmitting module faster than it can send the data to the host.
being held off by hardware or software flow control.
If the RF data rate is set higher than the interface data rate of the module, the module will
If the host does not allow the module to transmit data out from the DO buffer because of
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