Digi XBee User manual

Digi International Inc.
11001 Bren Road East
Minnetonka, MN 55343
877 912-3444 or 952 912-3444
http://www.digi.com
XBee®/XBee-PRO® ZB RF Modules
ZigBee RF Modules by Digi International
Models: XBEE2, XBEEPRO2, PRO S2B
Hardware: S2 and S2B
Firmware Versions:
- 20xx - Coordinator - AT/Transparent Operation
- 21xx - Coordinator - API Operation
- 22xx - Router - AT/Transparent Operation
- 23xx - Router - API Operation
- 28xx - End Device - AT/Transparent Operation
- 29xx - End Device - API Operation
90000976_M
9/25/12

XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternational,Inc. 2
© 2012 Digi International, Inc. All rights reserved
Nopartofthecontentsofthismanualmaybetransmittedorreproducedinany
formorbyanymeanswithoutthewrittenpermissionofDigiInternational,Inc.
ZigBee®isaregisteredtrademarkoftheZigBeeAlliance.
XBee®andXBee‐PRO®areregisteredtrademarksofDigiInternational,Inc.
Technical Support: Phone: [phone] toll-free U.S.A. & Canada
[phone] Worldwide
8:00 am - 5:00 pm [U.S. Mountain Time]
Online Support: http://www.digi.com/support/eservice/login.jsp
Email: [email protected]m

Contents
XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternaitonal,Inc. 3
Overview 6
What's New in 2x7x 6
Firmware 6
Manual 7
Key Features 8
Worldwide Acceptance 8
Specifications 9
Hardware Specs for Programmable Variant 10
Mechanical Drawings 10
SIF Header Interface 11
Mounting Considerations 12
Pin Signals 13
EM250 Pin Mappings 14
Design Notes 14
Power Supply Design 14
Recommended Pin Connections 15
Board Layout 15
Electrical Characteristics 17
Module Operation for Programmable Variant 17
XBEE Programmable Bootloader 19
Overview 19
Bootloader Software Specifics 19
Bootloader Menu Commands 23
Firmware Updates 24
Output File configuration 24
RF Module Operation 26
Serial Communications 26
UART Data Flow 26
Serial Buffers 26
Serial Flow Control 27
Serial Interface Protocols 28
Modes of Operation 30
Idle Mode 30
Transmit Mode 30
Receive Mode 31
Command Mode 31
Sleep Mode 32
XBee ZigBee Networks 33
Introduction to ZigBee 33
ZigBee Stack Layers 33
Networking Concepts 33
Device Types 33
PAN ID 34
Operating Channel 35
ZigBee Application Layers: In Depth 35
Application Support Sublayer (APS) 35
Application Profiles 35
Coordinator Operation 36
Forming a Network 36
Channel Selection 36
PAN ID Selection 36
Security Policy 37
Persistent Data 37
XBee ZB Coordinator Startup 37
Permit Joining 38
Resetting the Coordinator 38
Leaving a Network 38
Replacing a Coordinator (Security Disabled Only) 39
Example: Starting a Coordinator 39
Example: Replacing a Coordinator (security disabled) 40
Router Operation 40
Discovering ZigBee Networks 40
Joining a Network 40
Authentication 40
Persistent Data 41
XBee ZB Router Joining 41
Permit Joining 43
Joining Always Enabled 43
Joining Temporarily Enabled 43
Router Network Connectivity 43
Leaving a Network 45
Resetting the Router 46
Example: Joining a Network 46
End Device Operation 46
Discovering ZigBee Networks 46
Joining a Network 47
Parent Child Relationship 47
End Device Capacity 47
Authentication 47
Persistent Data 47
Orphan Scans 47
XBee: ZB End Device Joining 48
Parent Connectivity 49
Resetting the End Device 49
Leaving a Network 49
Example: Joining a Network 49
Channel Scanning 50

Contents
XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternaitonal,Inc. 4
Managing Multiple ZigBee Networks 50
PAN ID Filtering 50
Preconfigured Security Keys 50
Permit Joining 51
Application Messaging 51
Transmission, Addressing, and Routing 52
Addressing 52
64-bit Device Addresses 52
16-bit Device Addresses 52
Application Layer Addressing 52
Data Transmission 52
Broadcast Transmissions 53
Unicast Transmissions 53
Data Transmission Examples 55
RF Packet Routing 56
Link Status Transmission 57
AODV Mesh Routing 58
Many-to-One Routing 60
Source Routing 60
Encrypted Transmissions 63
Maximum RF Payload Size 63
Throughput 64
ZDO Transmissions 64
ZigBee Device Objects (ZDO) 64
Sending a ZDO Command 65
Receiving ZDO Commands and Responses 65
Transmission Timeouts 66
Unicast Timeout 67
Extended Timeout 67
Transmission Examples 68
Security 70
Security Modes 70
ZigBee Security Model 70
Network Layer Security 70
Frame Counter 71
Message Integrity Code 71
Network Layer Encryption and Decryption 71
Network Key Updates 71
APS Layer Security 71
Message integrity Code 72
APS Link Keys 72
APS Layer Encryption and Decryption 72
Network and APS Layer Encryption 72
Trust Center 73
Forming and Joining a Secure Network 73
Implementing Security on the XBee 73
Enabling Security 74
Setting the Network Security Key 74
Setting the APS Trust Center Link Key 74
Enabling APS Encryption 74
Using a Trust Center 74
XBee Security Examples 75
Example 1: Forming a network with security (pre-con-
figured link keys) 75
Example 2: Forming a network with security (obtain-
ing keys during joining) 75
Network Commissioning and Diagnostics 77
Device Configuration 77
Device Placement 77
Link Testing 77
RSSI Indicators 78
Device Discovery 78
Network Discovery 78
ZDO Discovery 78
Joining Announce 78
Commissioning Pushbutton and Associate LED 78
Commissioning Pushbutton 79
Associate LED 80
Managing End Devices 82
End Device Operation 82
Parent Operation 82
End Device Poll Timeouts 83
Packet Buffer Usage 83
Non-Parent Device Operation 83
XBee End Device Configuration 84
Pin Sleep 84
Cyclic Sleep 86
Transmitting RF Data 89
Receiving RF Data 89
IO Sampling 90
Waking End Devices with the Commissioning Pushbut-
ton 90
Parent Verification 90
Rejoining 90
XBee Router/Coordinator Configuration 90
RF Packet Buffering Timeout 91
Child Poll Timeout 91

Contents
XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternaitonal,Inc. 5
Transmission Timeout 91
Putting it all Together 92
Short Sleep Periods 92
Extended Sleep Periods 92
Sleep Examples 92
XBee Analog and Digital IO Lines 94
IO Configuration 94
IO Sampling 94
Queried Sampling 96
Periodic IO Sampling 96
Change Detection Sampling 96
RSSI PWM 96
IO Examples 97
API Operation 98
API Frame Specifications 98
API Examples 100
API UART Exchanges 101
AT Commands 101
Transmitting and Receiving RF Data 101
Remote AT Commands 101
Source Routing 102
Supporting the API 102
API Frames 102
AT Command 102
AT Command - Queue Parameter Value 103
ZigBee Transmit Request 103
Explicit Addressing ZigBee Command Frame 105
Remote AT Command Request 107
Create Source Route 108
AT Command Response 109
Modem Status 109
ZigBee Transmit Status 110
ZigBee Receive Packet 111
ZigBee Explicit Rx Indicator 112
ZigBee IO Data Sample Rx Indicator 113
XBee Sensor Read Indicator 114
Node Identification Indicator 116
Remote Command Response 117
Over-the-Air Firmware Update Status 118
Route Record Indicator 119
Many-to-One Route Request Indicator 120
Sending ZigBee Device Objects (ZDO) Commands
with the API 121
Sending ZigBee Cluster Library (ZCL) Commands
with the API 123
Sending Public Profile Commands with the API 125
XBee Command Reference Tables 128
Module Support 138
Power up Module at 9600 Baud 138
X-CTU Configuration Tool 138
Customizing XBee ZB Firmware 138
Design Considerations for Digi Drop-In Networking
138
XBee Bootloader 138
Programming XBee Modules 139
Serial Firmware Updates 139
Invoke XBee Bootloader 139
Send Firmware Image 139
SIF Firmware Updates 140
Writing Custom Firmware 140
Regulatory Compliance 140
Enabling GPIO 1 and 2 141
Detecting XBee vs. XBee-PRO 141
Ensuring Optimal Output Power 141
Improving Low Power Current Consumption 142
XBee (non-PRO) Initialization: 142
When sleeping (end devices): 142
When waking from sleep (end devices): 142
Appendix A:Definitions 143
Appendix B:Agency Certifications 145
Appendix C:Migrating from ZNet 2.5 to XBee ZB 153
Appendix D:Additional Information 154

©2012DigiInternational,Inc. 6
1.Overview
This manual describes the operation of the XBee/XBee-PRO ZB RF module, which
consists of ZigBee firmware loaded onto XBee S2 and S2B hardware, models:
XBEE2, XBEEPRO2 and PRO S2B. The XBee/XBee-PRO ZB RF Modules are
designed to operate within the ZigBee protocol and 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 ISM 2.4 GHz frequency band and are compatible
with the following:
•XBee RS-232 Adapter
•XBee RS-485 Adapter
•XBee Analog I/O Adapter
•XBee Digital I/O Adapter
•XBee Sensor
•XBee USB Adapter
•XStick
•ConnectPort X Gateways
•XBee Wall Router.
The XBee/XBee-PRO ZB firmware release can be installed on XBee ZNet or ZB modules. The XBee ZB firmware is based
on the EmberZNet 3.x ZigBee PRO Feature Set mesh networking stack, while the XBee ZNet 2.5 firmware is based on
Ember's proprietary "designed for ZigBee" mesh stack (EmberZNet 2.5.x). ZB and ZNet 2.5 firmware are similar in
nature, but not over-the-air compatible. Devices running ZNet 2.5 firmware cannot talk to devices running the ZB firm-
ware.
What's New in 2x7x
Firmware
XBee/XBee-PRO ZB firmware includes the following new features (compared with 2x6x):
•Using Ember stack version 3.4.1.
•Support for the PRO S2B with temperature compensation and an overvoltage check. Within 15 seconds of
the supply voltage exceeding 3.9V, the API will emit a 0x08 modem status (Overvoltage) message, and 
then the AT/API versions will do a watchdog reset.
•ZDO pass-through added. If AO=3, then ZDO requests which are not supported by the stack will be 
passed out the UART.
•An attempt to send an oversized packet (256+ bytes) will result in a Tx Status message with a status code
of 0x74.
•End devices have two speed polling. 7.5 seconds is the slow rate, which switches to the fast rate to trans-
act with its parent. When transactions are done, it switches back to the slow rate.
•A new receive option bit (0x40) indicates if the packet came from an end device.
•Added extended timeout option since end devices need more time than routers to ack their packets.
•An option bit (0x01) was added to disable APS retries.
•If an end device has not had its polls answered for 5 secs, it will leave and attempt to rejoin the network.
•XBee S2B has a new TP command which returns the temperature compensation sensor reading in units of
Celsius degrees.
•The PP command returns the power dBm setting when PL4 is selected.
•The PO command sets the slow polling rate on end devices. Range is 1-0x1770 in units of 10 msec (10 
msec to 60 sec). Default is 0 which invokes a 100 msec delay.
•Rejoining now can proceed without a NR or NRO command after a Mgmt_Leave_req is processed.
•Command ranges were changed for the SC, IR, and LT commands.
•A PAN ID corruption problem was fixed.
See the 2x7x release notes for a complete list of new features and bug fixes at www.digi.com/support.

XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternational,Inc. 7
Manual
The XBee/XBee-PRO/S2B ZB 2x7x manual includes the following corrections over the 2x6x manual:
•Descriptions and specification for the PRO S2B.
•SIF Header Interface, pin 8 relabeled as pin 10.
•Pin mappings for pins 22 and 24 updated.
•New modem status codes were added.
•Corrections to the ZigBee Receive Packet description.
•Description changes for the SC, PL, PP, AO, IR, %V, and PO commands.
•Updates to Appendix B.

XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternational,Inc. 8
Key Features
Worldwide Acceptance
FCC Approval (USA) Refer to Appendix A for FCC Requirements. Systems that contain XBee®/
XBee-PRO® ZB RF Modules inherit Digi Certifications.
ISM (Industrial, Scientific & Medical) 2.4 GHz frequency band
Manufactured under ISO 9001:2000 registered standards
XBee®/XBee-PRO® ZB RF Modules are optimized for use in US, Canada, Europe, Australia, and
Japan (contact Digi for complete list of agency approvals).
High Performance, Low Cost
XBee
• Indoor/Urban: up to 133’ (40 m)
• Outdoor line-of-sight: up to 400’ (120 m)
• Transmit Power: 2 mW (3 dBm)
• Receiver Sensitivity: -96 dBm
XBee-PRO (S2)
• Indoor/Urban: up to 300’ (90 m), 200' (60
m) for International variant
• Outdoor line-of-sight: up to 2 miles (3200
m), 5000' (1500 m) for International variant
• Transmit Power: 50mW (17dBm), 10mW
(10dBm) for International variant
• Receiver Sensitivity: -102 dBm
XBee-PRO (S2B)
• Indoor/Urban: up to 300’ (90 m), 200' (60
m) for International variant
• Outdoor line-of-sight: up to 2 miles (3200
m), 5000' (1500 m) for International variant
• Transmit Power: 63mW (18dBm), 10mW
(10dBm) for International variant
• Receiver Sensitivity: -102 dBm
Advanced Networking & Security
Retries and Acknowledgements
DSSS (Direct Sequence Spread Spectrum)
Each direct sequence channel has over
65,000 unique network addresses available
Point-to-point, point-to-multipoint 
and peer-to-peer topologies supported
Self-routing, self-healing and fault-tolerant
mesh networking
Low Power
XBee
• TX Peak Current: 40 mA (@3.3 V)
• RX Current: 40 mA (@3.3 V)
• Power-down Current: < 1 A
XBee-PRO (S2)
• TX Peak Current: 295mA (170mA for
international variant)
• RX Current: 45 mA (@3.3 V)
• Power-down Current: 3.5 A typical
@ 25 degrees C
XBee-PRO (S2B)
• TX Peak Current: 205mA (117mA for 
international variant)
• RX Current: 47 mA (@3.3 V)
• Power-down Current: 3.5 A typical 
@ 25 degrees C
Easy-to-Use
No configuration necessary for out-of box
RF communications
AT and API Command Modes for 
configuring module parameters
Small form factor
Extensive command set
Free X-CTU Software
(Testing and configuration software)
Free & Unlimited Technical Support

XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternational,Inc. 9
Specifications
SpecificationsoftheXBee®/XBee‐PRO®ZBRFModule
Specification XBee XBee-PRO (S2) XBee-PRO (S2B)
Performance
Indoor/Urban Range up to 133 ft. (40 m) Up to 300 ft. (90 m), up to 200 ft (60 m)
international variant Up to 300 ft. (90 m), up to 200 ft (60 m) international variant
Outdoor RF line-of-sight
Range up to 400 ft. (120 m) Up to 2 miles (3200 m), up to 5000 ft (1500 m) international variant Up to 2 miles (3200 m), up to 5000 ft (1500 m) international variant
Transmit Power Output 2mW (+3dBm), boost mode enabled
1.25mW (+1dBm), boost mode
disabled
50mW (+17 dBm)
10mW (+10 dBm) for International
variant
63mW (+18 dBm)
10mW (+10 dBm) for International variant
RF Data Rate 250,000 bps 250,000 bps 250,000 bps
Data Throughput up to 35000 bps (see chapter 4) up to 35000 bps (see chapter 4) up to 35000 bps (see chapter 4)
Serial Interface Data Rate
(software selectable)
1200 bps - 1 Mbps
(non-standard baud rates also
supported)
1200 bps - 1 Mbps
(non-standard baud rates also
supported)
1200 bps - 1 Mbps
(non-standard baud rates also supported)
Receiver Sensitivity -96 dBm, boost mode enabled
-95 dBm, boost mode disabled -102 dBm -102 dBm
Power Requirements
Supply Voltage 2.1 - 3.6 V 3.0 - 3.4 V 2.7 - 3.6 V
Operating Current
(Transmit, max output
power)
40mA (@ 3.3 V, boost mode
enabled)
35mA (@ 3.3 V, boost mode
disabled)
295mA (@3.3 V)
170mA (@3.3 V) international variant
205mA, up to 220 mA with programmable
variant (@3.3 V)
117mA, up to 132 mA with programmable
variant (@3.3 V), International variant
Operating Current
(Receive))
40mA (@ 3.3 V, boost mode
enabled)
38mA (@ 3.3 V, boost mode
disabled) 45 mA (@3.3 V) 47 mA, up to 62 mA with programmable
variant (@3.3 V)
Idle Current (Receiver off) 15mA 15mA 15mA
Power-down Current < 1 uA @ 25oC3.5A typical @ 25oC3.5A typical @ 25oC
General
Operating Frequency
Band ISM 2.4 GHz ISM 2.4 GHz ISM 2.4 GHz
Dimensions 0.960” x 1.087” (2.438cm x 2.761cm) 0.960 x 1.297 (2.438cm x 3.294cm) 0.960 x 1.297 (2.438cm x 3.294cm)
Operating Temperature -40 to 85º C (industrial) -40 to 85º C (industrial) -40 to 85º C (industrial)
Antenna Options IntegratedWhipAntenna,Embedded PCB Antenna, RPSMA, or U.FL
Connector
Integrated Whip Antenna, Embedded
PCB Antenna, RPSMA or U.FL
Connector Integrated Whip Antenna, Embedded PCB
Antenna, RPSMA or U.FL Connector
Networking & Security
Supported Network
Topologies Point-to-point, Point-to-multipoint, Peer-to-peer, and Mesh Point-to-point, Point-to-multipoint, Peer- to-peer, and Mesh Point-to-point, Point-to-multipoint, Peer-to- peer, and Mesh
Number of Channels 16 Direct Sequence Channels 14 Direct Sequence Channels 15 Direct Sequence Channels
Channels 11 to 26 11 to 24 11 to 25
Addressing Options PAN ID and Addresses, Cluster IDs
and Endpoints (optional) PANIDandAddresses,ClusterIDsand Endpoints (optional) PAN ID and Addresses, Cluster IDs and Endpoints (optional)
Agency Approvals
United States (FCC Part
15.247) FCC ID: OUR-XBEE2 FCC ID: MCQ-XBEEPRO2 FCC ID: MCQ-PROS2B
Industry Canada (IC) IC: 4214A-XBEE2 IC: 1846A-XBEEPRO2 IC: 1846A-PROS2B
Europe (CE) ETSI ETSI (International variant) ETSI (10 mW max)

XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternational,Inc. 10
Hardware Specs for Programmable Variant
The following specifications need to be added to the current measurement of the previous table if the module
has the programmable secondary processor. For example, if the secondary processor is running and
constantly collecting DIO samples at a rate while having the RF portion of the XBEE sleeping the new current
will be I total = Ir2 + I0, where Ir2 is the runtime current of the secondary processor and Isis the sleep current
of the RF portion of the module of the XBEE-PRO (S2B) listed in the table below.
Mechanical Drawings
MechanicaldrawingsoftheXBee®/XBee‐PRO®ZBRFModules(antennaoptionsnotshown)
.
Australia C-Tick C-Tick C-Tick
Japan
R201WW07215215
(Wire, chip, RPSMA, and U.FL
versions)
R210-101040
(PCB antenna version)
R201WW08215142 (international
variant)
Wire, chip, RPSMA, and U.FL versions
are certified for Japan. PCB antenna
version is not.
R201WW10215062 (international variant)
RoHS Compliant Compliant Compliant
Specificationsoftheprogrammablesecondaryprocessor
Optional Secondary Processor Specification
These numbers add to S2B specifications
(Add to RX, TX, and sleep currents depending on
mode of operation)
Runtime current for 32k running at 20MHz +14mA
Runtime current for 32k running at 1MHz +1mA
Sleep current +0.5uA typical
For additional specifications see Freescale Datasheet and
Manual MC9S08QE32
Minimum Reset low pulse time for EM250 +50 nS (additional resistor increases minimum time)
VREF Range 1.8VDC to VCC
SpecificationsoftheXBee®/XBee‐PRO®ZBRFModule
Specification XBee XBee-PRO (S2) XBee-PRO (S2B)

XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternational,Inc. 11
MechanicalDrawingsfortheRPSMAVari an t
SIF Header Interface
The XBee/XBee-PRO ZB modules include a SIF programming header that can be used with Ember's
programming tools to upload custom firmware images onto the XBee module. The SIF header orientation and
pinout are shown below.
A male header can be populated on the XBee that mates with Ember's 2x5 ribbon cable. The male header and
ribbon cables are available from Samtec:
2x5 Male Header - FTSH-105-01-F-DV-K
2x5 Ribbon Cable - FFSD-05-D-12.00-01-N

XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternational,Inc. 12
Mounting Considerations
The XBee module was designed to mount into a receptacle (socket) and therefore does not require any
soldering when mounting it to a board. The XBee-PRO Development Kits contain RS-232 and USB interface
boards which use two 20-pin receptacles to receive modules.
XBee‐PROModuleMountingtoanRS‐232InterfaceBoard.
The receptacles used on Digi development boards are manufactured by Century Interconnect. 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)
• Through-hole single-row receptacles - 
Mill-Max P/N: 831-43-0101-10-001000
• 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
Digi also recommends printing an outline of the module on the board to indicate the orientation the
module should be mounted.

XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternational,Inc. 13
Pin Signals
• Signal Direction is specified with respect to the module
• See Design Notes section below for details on pin connections.
PinAssignmentsfortheXBee/XBee‐PROModules
(Low‐assertedsignalsaredistinguishedwithahorizontallineabovesignalname.)
Pin # Name Direction Default State Description
1 VCC - - Power supply
2 DOUT Output Output UART Data Out
3 DIN / CONFIG Input Input UART Data In
4 DIO12 Both Disabled Digital I/O 12
5RESET Both Open-Collector with
pull-up Module Reset (reset pulse must beat least 200 ns)
6 RSSI PWM / DIO10 Both Output RX Signal Strength Indicator / Digital IO
7 DIO11 Both Input Digital I/O 11
8 [reserved] - Disabled Do not connect
9DTR
/ SLEEP_RQ/ DIO8 Both Input Pin Sleep Control Line or Digital IO 8
10 GND - - Ground
11 DIO4 Both Disabled Digital I/O 4
12 CTS / DIO7 Both Output Clear-to-SendFlowControl or Digital I/O 7. CTS, if
enabled, is an output.
13 ON / SLEEP Output Output Module Status Indicator or Digital I/O 9
14 VREF Input -
Not used for EM250. Used for programmable
secondary processor.
For compatibility with other XBEE modules, we
recommend connecting this pin voltage reference
if Analog sampling is desired.
Otherwise, connect to GND.
15 Associate / DIO5 Both Output Associated Indicator, Digital I/O 5
16 RTS / DIO6 Both Input Request-to-Send Flow Control, Digital I/O 6. RTS,
if enabled, is an input.
17 AD3 / DIO3 Both Disabled Analog Input 3 or Digital I/O 3
18 AD2 / DIO2 Both Disabled Analog Input 2 or Digital I/O 2
19 AD1 / DIO1 Both Disabled Analog Input 1 or Digital I/O 1
20 AD0 / DIO0 /
Commissioning Button Both Disabled Analog Input 0, Digital IO 0, or Commissioning Button

XBee®/XBee‐PRO®ZBRFModules
©2012DigiInternational,Inc. 14
EM250 Pin Mappings
The following table shows how the EM250 pins are used on the XBee.
* NOTE: These lines may not go to the external XBEE pins of the module if the programmable secondary processor
is populated.
Design Notes
The XBee modules do not specifically require any external circuitry or specific connections for proper
operation. However, there are some general design guidelines that are recommended for help in
troubleshooting and building a robust design.
Power Supply Design
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 a 1uF and 8.2pF capacitor are recommended to be
placed as near to pin1 on the PCB as possible. If using a switching regulator for your power supply, switching
frequencies above 500kHz are preferred. Power supply ripple should be limited to a maximum 250mV peak to
peak.
Note – For designs using the programmable modules an additional 10uF decoupling cap is recommended near
pin 1 of the module. The nearest proximity to pin 1 of the 3 caps should be in the following order: 8.2pf, 1uF
followed by 10uF.
EM250 Pin Number XBee Pin Number Other Usage
13 (Reset) 5* Connected to pin 8 on 2x5 SIF header.
19 (GPIO 11) 16*
20 (GPIO 12) 12*
21 (GPIO 0) 15
22 (GPIO 1)
XBee
Tied to ground (module identification)
XBee-PRO (S2)
Low-asserting shutdown line for output power compensation circuitry.
XBee-PRO (S2B)
Used to communicate with Temp Sensor and control Shutdown for low power mode.
24 (GPIO 2)
XBee
Not connected. Configured as output low.
XBee-PRO (S2)
Powers the output power compensation circuitry.
XBee-PRO (S2B)
Used to communicate with Temp Sensor and control Shutdown for low power mode.
25 (GPIO 3) 13
26 (GPIO 4 / ADC 0) 20 Connected to pin 9 on 2x5 SIF header.
27 (GPIO 5 / ADC 1) 19 Connected to pin 10 on 2x5 SIF header.
29 (GPIO 6 /ADC 2) 18
30 (GPIO 7 / ADC 3 17
31 (GPIO 8) 4
32 (GPIO 9) 2*
33 (GPIO 10) 3*
34 (SIF_CLK) Connected to pin 6 on 2x5 SIF header.
35 (SIF_MISO) Connected to pin 2 on 2x5 SIF header.
36 (SIF_MOSI) Connected to pin 4 on 2x5 SIF header.
37 (SIF_LOAD) Connected to pin 7 on 2x5 SIF header.
40 (GPIO 16) 7
41 (GPIO 15) 6
42 (GPIO 14) 9
43 (GPIO 13) 11

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Recommended Pin Connections
The only required pin connections are VCC, GND, DOUT and DIN. To support serial firmware updates, VCC,
GND, DOUT, DIN, RTS, and DTR should be connected.
All unused pins should be left disconnected. All inputs on the radio can be pulled high with 30k internal pull-up
resistors using the PR software command. No specific treatment is needed for unused outputs.
For applications that need to ensure the lowest sleep current, inputs should never be left floating. Use internal
or external pull-up or pull-down resistors, or set the unused I/O lines to outputs.
Other pins may be connected to external circuitry for convenience of operation including the Associate LED pin
(pin 15) and the Commissioning pin (pin 20). The Associate LED pin will flash differently depending on the
state of the module to the network, and a pushbutton attached to pin 20 can enable various join functions
without having to send UART commands. Please see the commissioning pushbutton and associate LED section
in chapter 7 for more details. The source and sink capabilities are limited to 4mA for all pins on the module.
The VRef pin (pin 14) is not used on this module. For compatibility with other XBee modules, we recommend
connecting this pin to a voltage reference if analog sampling is desired. Otherwise, connect to GND.
Board Layout
XBee modules do not have any specific sensitivity to nearby processors, crystals or other PCB components.
Other than mechanical considerations, no special PCB placement is required for integrating XBee radios except
for those with integral antennas. In general, Power and GND traces should be thicker than signal traces and be
able to comfortably support the maximum currents.
The radios are also designed to be self sufficient and work with the integrated and external antennas without
the need for additional ground planes on the host PCB. However, considerations should be taken on the choice
of antenna and antenna location. Metal objects that are near an antenna cause reflections and may reduce the
ability for an antenna to efficiently radiate. Using an integral antenna (like a wire whip antenna) in an enclosed
metal box will greatly reduce the range of a radio. For this type of application an external antenna would be a
better choice.
External antennas should be positioned away from metal objects as much as possible. Metal objects next to
the antenna or between transmitting and receiving antennas can often block or reduce the transmission
distance. Some objects that are often overlooked are metal poles, metal studs or beams in structures,
concrete (it is usually reinforced with metal rods), metal enclosures, vehicles, elevators, ventilation ducts,
refrigerators and microwave ovens.
The Wire Whip Antenna should be straight and perpendicular to the ground plane and/or chassis. It should
reside above or away from any metal objects like batteries, tall electrolytic capacitors or metal enclosures. If
the antenna is bent to fit into a tight space, it should be bent so that as much of the antenna as possible is
away from metal. Caution should be used when bending the antenna, since this will weaken the solder joint
where the antenna connects to the module. Antenna elements radiate perpendicular to the direction they
point. Thus a vertical antenna emits across the horizon.
Chip Antennas should not have any ground planes or metal objects above or below the module at the antenna
location. For best results the module should be in a plastic enclosure, instead of metal one. It should be placed
at the edge of the PCB to which it is mounted. The ground, power and signal planes should be vacant
immediately below the antenna section (See drawing for recommended keepout area).

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Electrical Characteristics
Note – The signal-ended ADC measurements are limited in their range and only guaranteed for accuracy in
the range 0 to VREFI. The nature of the ADC’s internal design allows for measurements outside of this range
(+/- 200mV), but the accuracy of such measurements are not guaranteed.
Module Operation for Programmable Variant
The S2B modules that have the programmable option populated have a secondary processor with 32k of flash
and 2k of RAM. This allows module integrators to put custom code on the XBEE module to fit their own unique
needs. The DIN, DOUT, RTS, CTS, and RESET lines are intercepted by the secondary processor to allow it to be
in control of the data transmitted and received. All other lines are in parallel and can be controlled by either
the EM250 or the MC9S08QE micro (see Block Diagram for details). The EM250 by default has control of
certain lines. These lines can be released by the EM250 by sending the proper command(s) to disable the
desired DIO line(s) (see XBEE Command Reference Tables).
In order for the secondary processor to sample with ADCs, the XBEE pin 14 (VREF) needs to be connected to
a reference voltage.
Digi provides a bootloader that can take care of programming the processor over the air or through the serial
interface. This means that over the air updates can be supported through an XMODEM protocol. The processor
can also be programmed and debugged through a one wire interface BKGD (Pin 8).
.
DCCharacteristicsoftheXBee/XBee‐PRO
Symbol 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 VCC >= 2.7 V - - 0.18*VCC V
VOH Output High Voltage VCC >= 2.7 V 0.82*VCC - - V
IIIN Input Leakage Current VIN = VCC or GND, all inputs, per pin - - 0.5uA uA
IOHS Output source current (standard) All digital outputs except
RSSI/PWM, DIO10, DIO4 4mA
IOHH Output source current (high
current) RSSI/PWM, DIO10, DIO4 digital outputs 8 mA
IOLS Output sink current (standard All digital inputs except
RSSI/PWM, DIO10, DIO4 4mA
IOLH Output sink current (high current) RSSI/PWM, DIO10, DIO4 digital outputs 8 mA
IOH + IOL Total output current for all I/O pins All digital outputs 40 mA
VREFI VREF Internal EM250 has an internal reference that is
fixed 1.19 1.2 1.21 V
VIADC ADC input voltage range 0 VREFI V
RIS Input impedance When taking a sample 1 M Ohm
RIInput Impedance When not taking a sample 10 M Ohm

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XBEE Programmable Bootloader
Overview
The Xbee Programmable module is equipped with a Freescale MC9S08QExx application processor. This
application processor comes with a supplied bootloader. The following section describes how to interface the
customer's application code running on this processor to the XBee Programmable module's supplied
bootloader.
This section discusses how to initiate firmware updates using the supplied bootloader for wired and over-the-
air updates.
Bootloader Software Specifics
Memory Layout
Figure 1 shows the memory map for the MC9S08QE32 application processor.
The supplied bootloader occupies the bottom pages of the flash from 0xF200 to 0xFFFF. Application
code cannot write to this space.
The application code can exist in Flash from address 0x8400 to 0xF1BC. 1k of Flash from 0x8000 to
0x83FF is reserved for Non Volatile Application Data that will not be erased by the bootloader during a
flash update.
A portion of RAM is accessible by both the application and the bootloader. Specifically, there is a
shared data region used by both the application and the bootloader that is located at RAM address
0x200 to 0x215. Application code should not write anything to AppResetCause or BLResetCause unless
informing the bootloader of the impending reset reason.

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