Digi XBee User manual

XBee/XBee-PRO®
DigiMesh 2.4 RF Modules
User Manual
90000991_K

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Revision Record
Revision Date (MM/DD/YY) Description
K 5/2/2014 Quality revision

© 2014 Digi International Inc. iii
XBee/XBee-PRO®DigiMesh 2.4 User Manual
Table of Contents
General Information about the XBee/XBee-PRO DigiMesh 2.4 RF Module . . . . . . . .8
Key Features of the XBee/XBee-PRO 2.4 DigiMesh. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Worldwide Acceptance of the XBee/XBee-PRO 2.4 DigiMesh. . . . . . . . . . . . . . . . . . . . . . . . . 8
Specifications of the XBee/XBee-PRO 2.4 DigiMesh . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Mechanical Drawings of the XBee/XBee-PRO 2.4 DigiMesh. . . . . . . . . . . . . . . . . . . . . . . . . 10
Mounting Considerations for the XBee/XBee-PRO DigiMesh 2.4. . . . . . . . . . . . . . . . . . . . . . 11
XBee/XBee-PRO DigiMesh 2.4 Pin Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Recommended Pin Connections for XBee/XBee-PRO DigiMesh 2.4. . . . . . . . . . . . . . . . . 12
XBee DigiMesh 2.4 Design Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
XBee Board Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
XBee Power Supply Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
XBee Antenna Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
XBee/XBee-PRO® DigiMesh 2.4 Electrical Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . 15
XBee/XBee-PRO Module Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Serial Communications for the XBee RF Module. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
XBee UART Data Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
XBee Serial Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
XBee Serial Buffers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Serial Receive Buffer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Serial Transmit Buffer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
XBee Serial Flow Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
CTS Flow Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
RTS Flow Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
XBee Serial Interface Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Transparent Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
API Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
A Comparison of Transparent and API Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Idle Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Transmit Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Receive Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Command Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
AT Command Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Sleep Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

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XBee/XBee-PRO DigiMesh 2.4 Advanced Application Features . . . . . . . . . . . . . . . .26
XBee Remote Configuration Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Sending a Remote Command to XBee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Applying Changes On Remote XBee Devices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
XBee Remote Command Responses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
XBee Network Commissioning and Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
XBee Device Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
XBee Network Link Establishment and Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Building Aggregate Routes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Node Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
XBee Device Placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Link Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
RSSI Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
XBee Network Discovery. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Neighbor Polling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Link Reliability of the XBee DigiMesh 2.4 RF Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Network Link Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Link Testing Between Adjacent Devices. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Trace Routing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
NACK Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
XBee Commissioning Pushbutton and Associate LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Commissioning Pushbutton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Associate LED. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Diagnostics Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
XBee/ XBee-PRO DigiMesh 2.4 I/O Line Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
I/O Samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Queried Sampling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
XBee Periodic I/O Sampling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
XBee Digital I/O Change Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
XBee/XBee-PRO DigiMesh 2.4 Networking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
DigiMesh Feature Set . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
DigiMesh Networking Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Device Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

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Network ID . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Operating Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
DigiMesh Data Transmission and Routing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Unicast Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Broadcast Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Route Discovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Throughput . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
XBee DigiMesh 2.4 Transmission Timeouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Unicast One Hop Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Transmitting a Broadcast. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Transmitting a Unicast with a Known Route. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Transmitting a Unicast with an Unknown Route. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Transmitting a Unicast with a Broken Route . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
XBee/XBee-PRO DigiMesh 2.4 Sleep Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
DigiMesh Sleep Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Normal Mode (SM=0). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Asynchronous Pin Sleep Mode (SM=1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Asynchronous Cyclic Sleep Mode (SM=4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Asynchronous Cyclic Sleep with Pin Wake Up Mode (SM=5). . . . . . . . . . . . . . . . . . . . . . . . 47
Synchronous Sleep Support Mode (SM=7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Synchronous Cyclic Sleep Mode (SM=8). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
XBee Asynchronous Sleep Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
DigiMesh Wake Timer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
DigiMesh Sleeping Routers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Coordinating Sleep Modes in the DigiMesh Network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
DigiMesh Synchronization Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Becoming a Sleep Coordinator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Sleep Guard Times. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Auto-Early Wake-Up Sleep Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
XBee DigiMesh Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Selecting Sleep Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Starting a Sleeping DigiMesh Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53

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Adding a New Node to an Existing Network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Changing Sleep Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
XBee DigiMesh Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Query Sleep Cycle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Sleep Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Missed Sync Messages Command. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Sleep Status API Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
XBee/XBee-PRO Command Reference Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
XBee/XBee-PRO DigiMesh 2.4 API Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
XBee API Frame Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
XBee API Operation (AP parameter = 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
XBee API Operation-with Escape Characters (AP parameter = 2) . . . . . . . . . . . . . . . . . . . . 69
XBee Escape Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
XBee UART Frame Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Checksum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
XBee API UART Exchanges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
AT Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Transmitting and Receiving RF Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Remote AT Commands. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Supporting the XBee API. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
XBee Frame Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
AT Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
AT Command - Queue Parameter Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Transmit Request . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Explicit Addressing Command Frame . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Remote AT Command Request. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
AT Command Response. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Modem Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Transmit Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Route Information Packet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Aggregate Addressing Update . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Receive Packet. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82

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Explicit Rx Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Data Sample Rx Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Node Identification Indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Remote Command Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Appendix A: XBee/XBee-PRO Terms and Definitions . . . . . . . . . . . . . . . . . . . . . . . .87
Appendix B: Agency Certifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88
United States (FCC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
OEM Labeling Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
FCC Notices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
FCC-Approved Antennas (2.4 GHz). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
XBee RF Module High Gain Antenna Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Europe (ETSI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
OEM Labeling Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Restrictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Declarations of Conformity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Approved Antennas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Canada (IC). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Labeling Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Japan (Telec) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Labeling Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Australia (C-Tick). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Labeling Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Appendix C: Additional Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .96
1-Year Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96

© 2014 Digi International Inc. 8
XBee/XBee-PRO®DigiMesh 2.4 User Manual
General Information about the XBee/XBee-PRO
DigiMesh 2.4 RF Module
The XBee®and XBee-PRO®DigiMesh 2.4 RF Modules were engineered to support the unique
needs of low-cost, low-power wireless sensor networks. The modules require minimal power and
provide reliable delivery of data between remote devices. The modules operate within the SMT
2.4 MHz frequency band.
Key Features of the XBee/XBee-PRO 2.4
DigiMesh
The following table highlights the key features of the XBee DigiMesh 2.4 RF Module:
Worldwide Acceptance of the XBee/XBee-PRO 2.4 DigiMesh
Our XBee DigiMesh 2.4 RF modules meet the following standards:
• USA FCC approval (refer to Appendix B for FCC requirements)
• Systems that contain XBee-PRO®DigiMesh 2.4 RF Modules inherit Digi
certifications.
• ISM (Industrial, scientific, and medical) 2.4 GHz frequency band
High performance, low cost Low power
XBee
• Indoor/Urban: up to 100 ft. (30 m)
• Outdoor line-of-sight: up to 300 ft. (100
m)
• Transmit power output: 1 mW (0 dBm)
• Receiver sensitivity: -92 dBm
XBee-PRO
• Indoor/Urban: up to 300 ft (100 m)
• Outdoor line-of-sight: up to 1 mile (1500
m)
• Transmit power output: 100 mW (20 dBm)
EIRP
• Receiver sensitivity: -100 dBm
• RF data rate: 250 kbps
XBee
• TX peak current: 45mA (@ 3.3V)
• Power down current (cyclic sleep): <50 µA
• Power down current (pin sleep): <10 µA
XBee-PRO
• TX peak current: 250 mA (150 mA for
international variant)
• RX current: 55 mA (@ 3.3V)
• Power down current (cyclic sleep): <50 µA
• Power down current (pin sleep): <10 µA
Advanced networking and security Easy to use
• Retries and acknowledgements
• Optional self-routing, self-healing mesh
networking available
• DSSS (Direct Sequencing Spread
Spectrum)
• No configuration necessary for out of box
RF communications
• AT and API command modes for
configuring module
• Small form factor

© 2014 Digi International Inc. 9
XBee/XBee-PRO®DigiMesh 2.4 User Manual
• Manufactured under ISO 9001:2000 registered standards
• XBee-PRO DigiMesh 2.4 RF Modules are optimized for use in U.S. and Canada (contact Digi for
complete list of agency approvals.
Specifications of the XBee/XBee-PRO 2.4 DigiMesh
The following table discusses the hardware and mechanical specifications of the XBee-PRO
DigiMesh 2.4 RF Module:
Specification XBee XBee-PRO
Performance
Indoor/Urban range Up to 100 ft. (30 m) Up to 300 ft. (90 m), up to 200 ft. (60 m)
intl. variant
Outdoor RF line of sight range Up to 300 ft. (90 m)
Up to 1 mile (1.5 km), w/ 2.0 dB dipole
antenna
Up to 6 miles (10 km) w/ high gain
antenna
Transmit power output 1 mW (0 dBm) 63 mW (18 dBm)*
10 mW (10 dBm) for international variant
RF data rate 250 kpbs 250 kpbs
Serial interface data rate
(software selectable)
1200 bps - 250 kbps
(non-standard baud rates also
supported)
1200 bps-250 kbps (non-standard baud
rates also supported)
Receiver sensitivity -92 dBm (1% packet error rate) -100 dBm (1% packet error rate)
Power requirements
Supply voltage 2.8 - 3.4 VDC 2.8 - 3.4 VDC
Transmit current 45 mA (@ 3.3 V)
250 mA (@ 3.3 V) (150 mA for
international variant)
RPSMA module only: 340 mA (@ 3.3 V)
(180 mA for international variant)
Idle / Receive current 50 mA (@ 3.3 V) 55 mA (@ 3.3 V)
Power down current (pin sleep) <10 µA <10 µA
Power down current (cyclic
sleep) <50 µA <50 µA
General
Operating frequency band ISM 2.4 GHz ISM 2.4 GHz
Dimensions 0.960” x 1.087” (2.438 cm x 2.761 cm) 0.960” x 1.297” (2.438 cm x 3.294 cm)
Operating temperature -40 to 85 C (Industrial), 0 to 95% non -
condensing -40 to 85 C (Industrial), 0 to 95% non - condensing
Antenna options 1/4 wave wire antenna, embedded PCB antenna, RPSMA RF connector, U.FL RF
connector
1/4 wave wire antenna, RPSMA RF
connector, U.FL RF connector
Network and security
Supported network topologies Mesh, point-to-point, point-to-
multipoint, peer-to-peer Mesh, point-to-point, point-to-multipoint, peer-to-peer
Number of Channels (software
selectable) 16 direct sequence channels 12 direct sequence channels
Addressing Options PAN ID, channel and 64-bit addresses PAN ID, channel and 64-bit addresses
Encryption 128 bit AES 128 bit AES

© 2014 Digi International Inc. 10
XBee/XBee-PRO®DigiMesh 2.4 User Manual
1 See Appendix B for region-specific certification requirements
Mechanical Drawings of the XBee/XBee-PRO 2.4 DigiMesh
Mechanical drawings of the XBee-PRO®RF Modules (antenna options not shown)
Mechanical drawing for the RPSMA variant
Agency approvals
United States (FCC Part
15.247) OUR-XBEE OUR-XBEEPRO
Industry Canada (IC) 4214A XBEE 4214A XBEEPRO
Europe (CE) ETSI ETSI (max 10dBm transmit power
output)*
RoHS Lead-free and RoHS compliant Lead-free and RoHS compliant
Japan R201WW07215214 R201WW08215111” (max. 10 dBm
transmit power output)*
Australia C -Tick C - Tick

© 2014 Digi International Inc. 11
XBee/XBee-PRO®DigiMesh 2.4 User Manual
Mounting Considerations for the XBee/XBee-PRO DigiMesh 2.4
The XBee/XBee-PRO®DigiMesh 2.4 RF Module (through-hole) is designed to be mounted into a
receptacle (socket) and does not require any soldering when mounting it to a board. The
development kits contain RS-232 and USB interface boards that use two 20-pin receptacles to
receive modules.
XBee/XBee-PRO DigiMesh 2.4 RF module mounting to an RS-232 Interface Board.
The receptacles on Digi development boards are manufactured by Century Interconnect and
Samtec. Several other manufacturers provide comparable mounting solutions; However, Digi
currently uses the following receptacles:
• Through-hole single-row receptacles-Samtec P/N: MMS-110-01-L-SV (or equivalent)
• Surface-mount double-row receptacles-Century Interconnect P/N: CPRMSL20-D-0-1 (or
equivalent)
• Surface-mount single-row receptacles-Samtec P/N: SMM-110-02-SM-S
Note: Digi recommends that you print an outline of the module on the board to indicate the
correct orientation for mounting the module.
XBee/XBee-PRO DigiMesh 2.4 Pin Signals
The following table shows the XBee/XBee-PRO®DigiMesh 2.4 RF Module pin signals and
descriptions:
Pin # Name Direction Description
1 Vcc - Power supply
2 DOUT Output UART data out
3DIN/
CONFIG Input UART data in
4 DIO12 Either Digital I/O 12
5 RESET Input/Open
drain output
Module reset (reset pulse must be at least
100 us. This must be driven as an open
drain/collector. The module will drive this
line low when a reset occurs. This line
should never be driven high.)
6 PWM0/RSSI/DIO10 Either PWM output 0 / RX signal strength
indicator / Digital I/O
7 PWM/DIO11 Either PWM output 1 / Digital I/O 11

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XBee/XBee-PRO®DigiMesh 2.4 User Manual
Note:
• Signal direction is specified with respect to the module
• Module includes a 50 kpull-up resistor attached to RESET
• Several of the input pull-ups can be configured using the PR command
• Unused pins should be left disconnected
Recommended Pin Connections for XBee/XBee-PRO DigiMesh 2.4
The only required pin connections are VCC, GND, DOUT and DIN. To support serial firmware
updates, VCC, GND, DOUT, DIN, RTS, and DTR need to be connected.
All unused pins need to be left disconnected. All inputs on the radio can be pulled high with
internal pull-up resistors using the PR software command. No specific treatment is needed for
unused outputs.
Other pins can be connected to external circuitry for convenience of operation including the
Associate LED pin (pin 15) and the commissioning button pin (pin 20). The Associate LED pin will
flash differently depending on the state of the module, and a pushbutton attached to pin 20 can
enable various deployment and troubleshooting functions without having to send UART
commands.
If analog sampling is desired, attach the VRef pin (pin 14) to a voltage reference.
Note:
• Minimum pin connections on the XBee/XBee-PRO 2.4 DigiMesh: VCC, GND, DOUT & DIN
• Minimum connections on the XBee/XBee-PRO DigiMesh 2.4 for updating firmware: VCC, GND,
DOUT, DIN, RTS & DTR
8 [reserved] - Do not connect
9DTR / SLEEP_RQ/
DIO8 Either Pin sleep control line or Digital I/O 8
10 GND - Ground
11 AD4/DIO4 Either Analog input 4 or Digital I/O 4
12 CTS/
DIO7 Either Clear-to-send flow control or Digital I/O 7
13 ON/
SLEEP Output Module Status Indicator or Digital I/O 9
14 VREF - This line must be connected if analog I/O sampling is desired. Must be between 2.6
V and Vcc.
15 Associate / DIO5/AD5 Either Associated indicator, Digital I/O 5
16 RTS/
DIO6 Either Request-to-send flow control, Digital I/O 6
17 AD3 / DIO3 Either Analog input 3 or Digital I/O 3
18 AD2 / DIO2 Either Analog input 2 or Digital I/O 2
19 AD1 / DIO1 Either Analog input 1 or Digital I/O 1
20 AD0 / DIO0 /
Commissioning Button Either Analog input 0, Digital I/O 0, or Commissioning button
Pin # Name Direction Description

© 2014 Digi International Inc. 13
XBee/XBee-PRO®DigiMesh 2.4 User Manual
XBee DigiMesh 2.4 Design Notes
The XBee modules do not require any external circuitry or specific connections for proper
operation. However, there are some general design guidelines that are recommended for
troubleshooting and building a robust design.
XBee Board Layout
XBee modules are designed to be self sufficient and have minimal sensitivity to nearby
processors, crystals or other PCB components. As with all PCB designs, power and ground traces
should be thicker than signal traces and should be able to comfortably support the maximum
current specifications. No other special PCB design considerations are required for integrating
XBee radios except in the antenna section.
XBee Power Supply Design
A poor power supply can lead to poor radio performance, especially if the supply voltage is not
kept within tolerance or is excessively noisy. To help reduce noise, place a 1.0 uF and 8.2pF
capacitor as near to pin one on the PCB as possible. If you are using a switching regulator for
your power supply, switch the frequencies above 500kHz. The power supply ripple needs to be
limited to a maximum 100mV peak to peak.
XBee Antenna Performance
Antenna location is an important consideration for optimal performance. For optimal antenna
performance, see the following placement tips and suggestions:
Point your antenna up vertically (up right):
Antennas radiate and receive the best signal perpendicular to the direction they point, thus, a
vertical antenna's radiation pattern is strongest across the horizon.
Position antennas away from metal objects whenever possible:
Metal objects between the transmitter and receiver can block the radiation path or reduce the
transmission distance. Objects that are often overlooked include metal poles, metal studs,
structure beams, concrete (it is usually reinforced with metal rods).
Use an external antenna if the XBee device is placed inside a metal enclosure:
Common objects that have metal enclosures include vehicles, elevators, ventilation ducts,
refrigerators, microwave ovens, batteries, and tall electrolytic capacitors.
Do not place XBee modules with the chip or integrated PCB Antennas inside a metal
enclosure:
There should not be any ground planes or metal objects above or below the antenna. For best
results, place the XBee at the edge of the host PCB on which it is mounted. Ensure that the
ground, power, and signal planes are vacant immediately below the antenna section. It is
recommended that you allow a “keepout” area, which is shown in detail on the next page.

© 2014 Digi International Inc. 14
XBee/XBee-PRO®DigiMesh 2.4 User Manual
Keepout area for the XBee/XBee-PRO®DigiMesh 2.4 RF Module

© 2014 Digi International Inc. 15
XBee/XBee-PRO®DigiMesh 2.4 User Manual
XBee/XBee-PRO®DigiMesh 2.4 Electrical Characteristics
The following table displays the electrical voltage parameters of the XBee/XBee-PRO®DigiMesh
2.4 RF Module:
1 Maximum electrical operating range, not valid conversion range
1 All ACCURACY numbers are based on processor and system being in WAIT state (very little activity and no IO switching) and that adequate low-pass
filtering is present on analog input pins (filter with 0.01 F to 0.1 F capacitor between analog input and VREFL). Failure to observe these guidelines
may result in system or microcontroller noise causing accuracy errors which will vary based on board layout and the type and magnitude of the activity. 
Data transmission and reception during data conversion may cause some degradation of these specifications, depending on the number and timing
of packets. It is advisable to test the ADCs in your installation if best accuracy is required.
2 RAS is the real portion of the impedance of the network driving the analog input pin. Values greater than this amount may not fully charge the input
circuitry of the ATD resulting in accuracy error.
3 Analog input must be between VREFL and VREFH for valid conversion. Values greater than VREFH will convert to $3FF.
4 The resolution is the ideal step size or 1LSB = (VREFH–VREFL)/1024
Symbols Parameter Condition Min Typical Max Units
VIL Input low voltage All digital inputs - - 0.2 *
VCC V
VIH Input high voltage All digital inputs 0.8 *
VCC - - V
VOL Output low voltage IOL = 2 mA, VCC >= 3.0 V -- 0.18*VC
CV
VOH Output high voltage IOH = 2 mA, VCC >= 3.0 V 0.82*V
CC --V
IIIN Input leakage current VIN = VCC or GND, all
inputs, per pin -- 0.5
A
Symbol Parameter Condition Min Typical Max Units
VREFH VREF-analog-to-digital
converter reference
range 2.08 - VDDAD V
IREF VREF-reference supply
current Enabled - 200 - A
Disabled or sleep mode - < 0.01 0.02 A
VINDC Analog input voltage VSSAD -
0.3 -VSSAD + 0.3 V
Symbol Parameter Condition Min Typical Max Units
RAS Source impedance at
input2-- 10k
VAIN Analog input voltage3VREFL VREFH V
RES Ideal resolution (1
LSB)42.08V > VDDAD > 3.6V 2.031 3.516 mV
DNL Differential non-
linearity5- ±0.5 ±1.0 LSB
INL Integral non-linearity6- ±0.5 ±1.0 LSB
EZS Zero-scale error7- ±0.4 ±1.0 LSB
FFS Full-scale error8- ±0.4 ±1.0 LSB
EIL Input leakage error9- ±0.05 ±5.0 LSB
ETU Total unadjusted error - ±1.1 ±2.5 LSB

© 2014 Digi International Inc. 16
XBee/XBee-PRO®DigiMesh 2.4 User Manual
5 Differential non-linearity is the difference between the current code width and the ideal code width (1LSB). The current code width is the difference
in the transition voltages to and from the current code.
6 Integral non-linearity is the difference between the transition voltage to the current code and the adjusted ideal transition voltage for the current
code. The adjusted ideal transition voltage is (Current Code.1/2)*(1/((VREFH+EFS).(VREFL+EZS))).
7 Zero-scale error is the difference between the transition to the first valid code and the ideal transition to that code. The Ideal transition voltage to a
given code is (Code.1/2)*(1/(VREFH.VREFL)).
8 Full-scale error is the difference between the transition to the last valid code and the ideal transition to that code. The ideal transition voltage to a
given code is (Code.1/2)*(1/(VREFH.VREFL)).
9 Input leakage error is error due to input leakage across the real portion of the impedance of the network driving the analog pin. Reducing the
impedance of the network reduces this error.
10 Total unadjusted error is the difference between the transition voltage to the current code and the ideal straight-line transfer function. This measure
of error includes inherent quantization error (1/2LSB) and circuit error (differential, integral, zero-scale, and full-scale) error. The specified value of
ETU assumes zero EIL (no leakage or zero real source impedance).

© 2014 Digi International Inc. 17
XBee/XBee-PRO®DigiMesh 2.4 User Manual
XBee/XBee-PRO Module Operation
The XBee module provides a serial interface to an RF link. The XBee module converts serial data
to RF data that is sent to any device in an RF network. In addition to RF data communication
devices, the XBee module provides a software interface for interacting with a variety of
peripheral functions, including I/O sampling, commissioning and management devices. The
following diagram illustrates the functionality of the XBee module.
Functionality of the XBee/XBee-PRO DigiMesh 2.4 RF Module
Serial Communications for the XBee RF Module
The XBee-PRO RF Modules interface to a host device through a logic-level asynchronous serial
port. Through its serial port, the module can communicate with any logic and voltage compatible
UART, or through a level translator to any serial device (for example, through a Digi proprietary
RS-232 or USB interface board).
XBee UART Data Flow
Devices that have a universal asynchronous receiver/transmitter (UART) interface can connect
directly to the pins of the RF modules as shown in the figure below.
System data flow diagram in a UART-interfaced environment (low-asserted signals distinguished with

© 2014 Digi International Inc. 18
XBee/XBee-PRO®DigiMesh 2.4 User Manual
horizontal line over signal name).
XBee Serial Data
Data enters the module UART through the DIN (pin 3) as an asynchronous serial signal. The
signal will idle high when no data is being transmitted.
Each data byte consists of a start bit (low), 8 data bits (least significant bit first) and a stop bit
(high). The following figure illustrates the serial bit pattern of data passing through the module.
UART data packet 0x1F (decimal number “31”) as transmitted through the RF module. Example data for-
mat is 8-N-1 (bits - parity - # of stop bits)
The module UART performs tasks such as timing and parity checking, which is needed for data
communications. Serial communications depend on the two UARTs to be configured with
compatible settings (baud rate, parity, start bits, stop bits, data bits).
XBee Serial Buffers
The XBee-PRO modules maintain buffers to collect received serial and RF data, which is
illustrated in the figure below. The serial receive buffer collects incoming serial characters and
holds them until they can be processed. The serial transmit buffer collects data that is received
via the RF link that will be transmitted out the UART.
Microcontroller Microcontroller
XBee
Module
XBee
Module
CMOS Logic (3.0-3.6V)
DOUT (data out)
DIN (data in)
CTS
RTS
CMOS Logic (3.0-3.6V)
DOUT (data out)
DIN (data in)
CTS
RTS
Microcontroller
Microcontroller
XBee
Module
XBee
Module
CMOS Logic (3.0-3.6V)
DOUT (data out)
DIN (data in)
CTS
RTS
CMOS Logic (3.0-3.6V)
DOUT (data out)
DIN (data in)
CTS
RTS

© 2014 Digi International Inc. 19
XBee/XBee-PRO®DigiMesh 2.4 User Manual
Process of XBee-PRO buffers collecting received serial data
Serial Receive Buffer
When serial data enters the RF module through the DIN Pin (pin 3), the data is stored in the
serial receive buffer until it can be processed. Under certain conditions, the module may not be
able to process data in the serial receive buffer immediately. If large amounts of serial data are
sent to the module, CTS flow control may be required to avoid overflowing the serial receive
buffer.
Cases in which the serial receive buffer may become full and possibly overflow:
1 If the module is receiving a continuous stream of RF data, the data in the serial receive buffer
will not be transmitted until the module is no longer receiving RF data.
2 For mesh networking firmware, if the module is transmitting an RF data packet, the module
may need to discover the destination address or establish a route to the destination. After
transmitting the data, the module may need to retransmit the data if an acknowledgment is
not received, or if the transmission is a broadcast. As a result, these issues could delay the
processing of data in the serial receive buffer.
Serial Transmit Buffer
When RF data is received, the data is moved into the serial transmit buffer and is sent out the
serial port. If the serial transmit buffer becomes full enough such that all data in a received RF
packet won’t fit in the serial transmit buffer, the entire RF data packet is dropped.
Cases in which the serial transmit buffer may become full resulting in dropped RF packets
1 If the RF data rate is set higher than the interface data rate of the module, the module could
receive data faster than it can send the data to the host. Even occasional transmissions from
a large number of modules can quickly add up and overflow the transmit buffer.
2 If the host does not allow the module to transmit data out from the serial transmit buffer
because of being held off by hardware flow control.
Serial
Receiver
Buffer
RF TX
Buffer Transmitter
RF Switch
Antenna
Port
Receiver
Serial Transmit
Buffer RF RX
Buffer
Processor
GND
DIN
VCC
DOUT
CTS
RTS

© 2014 Digi International Inc. 20
XBee/XBee-PRO®DigiMesh 2.4 User Manual
XBee Serial Flow Control
The RTS and CTS module pins provide RTS and/or CTS flow control. CTS flow control provides an
indication to the host to stop sending serial data to the module. RTS flow control allows the host
to signal the module to not send data in the serial transmit buffer out the UART. RTS and CTS
flow control are enabled using the D6 and D7 commands.
CTS Flow Control
If you enable the CTS flow control is enabled (D7 command) when the serial receive buffer is
filled with FT bytes, the module de-asserts CTS (sets it high) to signal to the host device to stop
sending serial data. CTS is re-asserted when less than FT-16 bytes are in the UART receive
buffer. (See command description for the FT command.)
RTS Flow Control
If you enable RTS flow control is enabled (D6 command), data in the serial transmit buffer will
not be sent out the DOUT pin as long as RTS is de-asserted (set high). Do not de-assert RTS for
long periods of time to avoid filling the serial transmit buffer. If an RF data packet is received,
and the serial transmit buffer does not have enough space for all of the data bytes, the entire RF
data packet will be discarded.
XBee Serial Interface Protocols
The XBee modules support both transparent and API (Application Programming Interface) serial
interfaces.
Transparent Operation
When a module operates in transparent mode, it acts as a serial line replacement. All UART data
received through the DIN pin is queued up for RF transmission. When a module receives RF
data, it sends the data out through the DOUT pin. You can set the configuration parameters
using the AT command mode interface.
Data is buffered in the serial receive buffer until one of the following causes the data to be
packetized and transmitted:
• No serial characters are received for the amount of time determined by the RO (Packetization
Timeout) parameter. If RO = 0, packetization begins when a character is received.
• The module receives the Command Mode Sequence (GT + CC + GT). If any characters were
placed in the serial receive buffer before the sequence, they are transmitted.
• The module receives the maximum number of characters that will fit in an RF packet.
API Operation
API operation is an alternative to transparent operation. The frame-based API extends the level
to which a host application can interact with the networking capabilities of the module. When
you operate the device in API mode, all data entering and leaving the UART is contained in
frames that define operations or events within the module.