Digi XBee, XBee-PRO User Manual
XBee/XBee-PRO DigiMesh 2.4
Radio Frequency (RF) Module
User Guide
Revision history—90000991
Revision Date Description
S January
2016
T February
2016
U June 2016
V June 2017 Modified regulatory and certification information as required by RED (Radio
W May 2018 Added note on range estimation. Changed ICto ISED.
Updated several AT commands.
Editorial revision to ATcommands.
Removed the 1S command. Fixed an error in the 0x90 frame table. Clarified
the routing table size.
Equipment Directive).
Trademarks and copyright
Digi, Digi International, and the Digi logo are trademarks or registered trademarks in the United
States and other countries worldwide. All other trademarks mentioned in this document are the
property of their respective owners.
© 2018 Digi International Inc. All rights reserved.
Disclaimers
Information in this document is subject to change without notice and does not represent a
commitment on the part of Digi International. Digi provides this document “as is,” without warranty of
any kind, expressed or implied, including, but not limited to, the implied warranties of fitness or
merchantability for a particular purpose. Digi may make improvements and/or changes in this manual
or in the product(s) and/or the program(s) described in this manual at any time.
Warranty
To view product warranty information, go to the following website:
www.digi.com/howtobuy/terms
Customer support
Gather support information: Before contacting Digi technical support for help, gather the following
information:
Product name and model
Product serial number (s)
Firmware version
Operating system/browser (if applicable)
Logs (from time of reported issue)
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
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Trace (if possible)
Description of issue
Steps to reproduce
Contact Digi technical support: Digi offers multiple technical support plans and service packages.
Contact us at +1 952.912.3444 or visit us at www.digi.com/support.
Feedback
To provide feedback on this document, email your comments to
Include the document title and part number (XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide,
90000991 W) in the subject line of your email.
techcomm@digi.com
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
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Contents
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
Worldwide acceptance 12
Antenna options 12
Part numbers 12
Technical specifications
Performance specifications 14
Power requirements 14
General specifications 15
Networking and security specifications 15
Regulatory conformity summary 15
Hardware
Mechanical drawings 18
Mounting considerations 19
Hardware diagram 20
Pin signals 21
Notes 22
Recommended pin connections 22
Design notes 22
Power supply design 22
Board layout 22
Antenna performance 23
Keepout area 23
DC characteristics 25
ADC operating characteristics 25
ADC timing and performance characteristics 26
Modes
Transparent and API operating modes 28
Transparent operating mode 28
API operating mode 28
Comparing Transparent and API modes 28
Additional modes 30
Command mode 30
Idle mode 30
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Receive mode 30
Sleep modes 30
Transmit mode 31
Command mode 31
Enter Command mode 31
Troubleshooting 31
Send AT commands 32
Response to AT commands 32
Apply command changes 32
Make command changes permanent 33
Exit Command mode 33
Configure the XBee/XBee-PRO DigiMesh 2.4
Software libraries 35
Configure the device using XCTU 35
XBee Network Assistant 35
Serial communication
Serial interface 38
UART data flow 38
Serial data 38
Serial buffers 39
Serial buffer issues 39
Serial flow control 40
CTS flow control 40
RTS flow control 40
Work with networked devices
Network commissioning and diagnostics 42
Local configuration 42
Remote configuration 42
Establish and maintain network links 43
Build aggregate routes 43
DigiMesh routing examples 43
Replace nodes 44
Test links in a network - loopback cluster 44
Test links between adjacent devices 45
Example 46
RSSI indicators 47
Discover all the devices on a network 47
Trace route option 47
NACK messages 49
The Commissioning Pushbutton 49
Associate LED 50
Monitor I/O lines 52
Queried sampling 52
Periodic I/O sampling 54
Detect digital I/O changes 54
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Network configurations
DigiMesh networking 57
Routers and end devices 58
Network identifiers 58
Operating channels 58
Unicast addressing 58
Broadcast addressing 59
Routing 59
Route discovery 59
DigiMesh throughput 60
Transmission timeouts 60
Sleep modes
About sleep modes 64
Asynchronous modes 64
Synchronous modes 64
Normal mode 64
Asynchronous pin sleep mode 65
Asynchronous cyclic sleep mode 65
Asynchronous cyclic sleep with pin wake up mode 65
Synchronous sleep support mode 65
Synchronous cyclic sleep mode 66
The sleep timer 66
Sleep coordinator sleep modes in the DigiMesh network 66
Synchronization messages 67
Become a sleep coordinator 69
Preferred sleep coordinator option 69
Resolution criteria and selection option 69
Commissioning Pushbutton option 70
Auto-early wake-up sleep option 72
Select sleep parameters 72
Start a sleeping synchronous network 72
Add a new node to an existing network 73
Change sleep parameters 74
Rejoin nodes that lose sync 74
Diagnostics 75
Query sleep cycle 75
Sleep status 75
Missed sync messages command 75
Sleep status API messages 76
AT commands
Special commands 78
AC (Apply Changes) 78
FR (Software Reset) 78
RE (Restore Defaults) 78
WR (Write) 78
MAC/PHY commands 79
CH (Operating Channel) 79
ID (Network ID) 79
MT(Broadcast Multi-Transmits) 79
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CA (CCA Threshold) 80
PL (TX Power Level) 80
RR (Unicast Mac Retries) 81
ED (Energy Detect) 81
BC (Bytes Transmitted) 81
DB (Last Packet RSSI) 82
GD (Good Packets Received) 82
EA (MAC ACK Failure Count) 82
TR (Transmission Failure Count) 83
UA (Unicasts Attempted Count) 83
%H (MAC Unicast One Hop Time) 83
%8 (MAC Broadcast One Hop Time) 83
Network commands 83
CE (Routing / Messaging Mode) 84
BH (Broadcast Hops) 84
NH (Network Hops) 84
DM (DigiMesh Options) 84
NN (Network Delay Slots) 85
MR (Mesh Unicast Retries) 85
Addressing commands 85
SH (Serial Number High) 85
SL (Serial Number Low) 86
DH (Destination Address High) 86
DL (Destination Address Low) 86
NI (Node Identifier) 86
NT (Network Discovery Back-off) 87
NO (Network Discovery Options) 87
CI (Cluster ID) 87
DE (Destination Endpoint) 88
SE (Source Endpoint) 88
Diagnostic - addressing commands 88
N? (Network Discovery Timeout) 88
Addressing discovery/configuration commands 89
AG (Aggregator Support) 89
DN (Discover Node) 89
ND (Network Discover) 90
FN (Find Neighbors) 90
Security commands 91
EE (Encryption Enable) 91
KY (AES Encryption Key) 91
Serial interfacing commands 91
BD (Baud Rate) 92
NB (Parity) 92
RO (Packetization Timeout) 93
FT (Flow Control Threshold) 93
AP (API Mode) 93
AO (API Options) 94
I/O settings commands 94
CB (Commissioning Pushbutton) 94
D0 (DIO0/AD0) 94
D1 (DIO1/AD1) 95
D2 (DIO2/AD2) 95
D3 (DIO3/AD3) 96
D4 (DIO4/AD4) 96
D5 (DIO5/AD5/ASSOCIATED_INDICATOR) 97
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D6 (DIO6/RTS) 97
D7 (DIO7/CTS) 98
D8 (DIO8/SLEEP_REQUEST) 98
D9 (ON_SLEEP) 99
P0 (DIO10/RSSI/PWM0 Configuration) 99
P1 (DIO11/PWM1 Configuration) 99
P2 (DIO12 Configuration) 100
PR (Pull-up/Down Resistor Enable) 100
M0 (PWM0 Duty Cycle) 101
M1 (PWM1 Duty Cycle) 101
LT (Associate LED Blink Time) 102
RP (RSSI PWM Timer) 102
I/O sampling commands 102
IC (DIO Change Detect) 102
IF (Sleep Sample Rate) 103
IR (Sample Rate) 103
IS (Force Sample) 104
Sleep commands 104
SM (Sleep Mode) 104
SO (Sleep Options) 105
SN (Number of Cycles Between ON_SLEEP) 106
SP (Sleep Time) 106
ST (Wake Time) 106
WH (Wake Host Delay) 107
Diagnostic - sleep status/timing commands 107
SS (Sleep Status) 107
OS (Operating Sleep Time) 108
OW (Operating Wake Time) 108
MS (Missed Sync Messages) 108
SQ (Missed Sleep Sync Count) 108
Command mode options 109
CC (Command Character) 109
CT (Command Mode Timeout) 109
CN (Exit Command Mode) 109
GT (Guard Times) 109
Firmware version/information commands 110
VL (Version Long) 110
VR (Firmware Version) 110
HV (Hardware Version) 110
DD (Device Type Identifier) 110
NP (Maximum Packet Payload Bytes) 111
CK (Configuration CRC) 111
Operate in API mode
API mode overview 113
API frame specifications 113
Calculate and verify checksums 115
Escaped characters in API frames 116
Frame descriptions 117
API frame exchanges 118
AT commands 118
Transmit and Receive RF data 118
Remote AT commands 119
Device Registration 119
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Code to support future API frames 120
Frame descriptions
Local AT Command Request - 0x08 122
Description 122
Format 122
Examples 122
Queue Local AT Command Request - 0x09 124
Description 124
Examples 124
Transmit Request - 0x10 126
Description 126
Transmit options bit field 127
Examples 127
Explicit Addressing Command Request - 0x11 129
Description 129
64-bit addressing 129
Reserved endpoints 129
Reserved cluster IDs 129
Reserved profile IDs 129
Transmit options bit field 130
Examples 131
Remote AT Command Request - 0x17 133
Description 133
Format 133
Examples 134
Local AT Command Response - 0x88 136
Description 136
Examples 136
Modem Status - 0x8A 138
Description 138
Modem status codes 139
Examples 140
Extended Transmit Status - 0x8B 141
Description 141
Route Information - 0x8D 143
Description 143
Format 143
Examples 144
Aggregate Addressing Update- 0x8E 145
Description 145
Examples 145
Receive Packet - 0x90 147
Description 147
Examples 148
Explicit Receive Indicator - 0x91 149
Description 149
Examples 150
I/O Sample Indicator- 0x92 151
Description 151
Examples 152
Node Identification Indicator - 0x95 154
Description 154
Examples 156
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Remote AT Command Response- 0x97 157
Description 157
Examples 158
Regulatory information
United States (FCC) 161
OEM labeling requirements 161
FCC notices 161
RF exposure statement 162
FCC-approved antennas (2.4 GHz) 162
Australia (C-Tick) 168
Labeling requirements 168
Brazil ANATEL 168
Modelo XBee-Pro S3B: 169
ISED (Innovation, Science and Economic Development Canada) 169
Labeling requirements 169
Europe 169
Maximum power and frequency specifications 170
OEM labeling requirements 170
Restrictions 170
Declarations of conformity 170
Approved antennas 171
Japan 171
Labeling requirements 172
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XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
The XBee/XBee-PRO DigiMesh 2.4 supports the unique needs of low-cost, low-power, wireless sensor
networks. The devices require minimal power and provide reliable data delivery between remote
devices. The devices operate within the ISM 2.4 MHz frequency band.
These devices support routing table sizes of 32 nodes. Networks larger than this send a route
discovery before each transmission. For larger networks this can be bandwidth expensive, so we offer
RF optimization services to help you properly configure a network.
Worldwide acceptance 12
Antenna options 12
Part numbers 12
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XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide Worldwide acceptance
Worldwide acceptance
We manufacture and certify the XBee/XBee-PRO DigiMesh 2.4s to certain industry standards. These
standards enable you to understand what the devices can do and where you can use them.
The Federal Communications Commission (FCC) approves the devices for use in the United States. For
details, see United States (FCC). If a system contains XBee/XBee-PRO DigiMesh 2.4s, the system
inherits Digi’s certifications.
The devices are certified to operate in the industrial, scientific, and medical (ISM) 2.4 GHz frequency
band.
We manufacture the devices under International Organization for Standardization (ISO) 9001:2000
registered standards.
We optimize the devices for use in the United States and Canada. For a complete list of agency
approvals, see Regulatory information.
Antenna options
Digi devices come in a variety of antenna options. The options that allow you to connect an external
antenna are reverse polarity standard subminiature assembly (RPSMA) and U.FL. Typically, you make
connections with either a dipole antenna with a U.FL connection, or a U.FL to RPSMA antenna adapter
cable.
RPSMA is the more traditional antenna connector, however, if the device is going to be inside of an
enclosure, you would need to locate the device near the edge of the enclosure to allow the connector
to pass through an available bulkhead. The RPSMA connector uses the same body as a regular SMA
connector, but changes the gender of the center conductor. The female RPSMA actually has a male
center conductor. We equip the XBee devices with an RPSMA female plug, while the antenna is an
RPSMA male jack.
The U.FL connection allows for connectivity to an external antenna. U.FL is a small antenna connection
for use with a pigtail connector. A pigtail is a short (typically 4 - 6 in) cable that either terminates into
an external antenna port such as an RPSMA, N or TNC connection or an antenna. You would attach the
RPSMA connector to a bulkhead. These options allow you to mount the device away from the edge of
the enclosure in your product and centrally locate the radio. U.FL is fragile and is not designed for
multiple insertions without a specialized tool to separate the pigtail without damaging the connector;
for more information, see http://www.digikey.com/product-detail/en/U.FL-LP(V)-N-2/HR5017-
ND/513034.
The other available antenna options are printed circuit board (PCB) and wire antennas. We form the
PCB antenna directly on the device with conductive traces. A PCB antenna performs about the same
as a wire antenna.
An integrated wire antenna consists of a small wire (about 80 mm) sticking up perpendicular to the
PCB. It uses a 1/4-wave wire that we solder directly to the PCB of the OEM device.
All Digi devices with antenna connectors have less than 0.1 dB loss; we do not consider one to be
"better" than the other in terms of reliability or insertion loss. RF device specifications such as -110
dBm receiver sensitivity, +3 0 dBm TX power, and so forth, already include any insertion loss due to
the soldered RF connector.
Part numbers
The part numbers for these devices are available at the following link:
www.digi.com/products/xbee-rf-solutions/modules/xbee-digimesh-2-4#partnumbers
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
12
Technical specifications
The following tables provide the device's technical specifications.
Performance specifications 14
Power requirements 14
General specifications 15
Networking and security specifications 15
Regulatory conformity summary 15
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Technical specifications Performance specifications
Performance specifications
The following table describes the performance specifications for the devices.
Note Range figure estimates are based on free-air terrain with limited sources of interference. Actual
range will vary based on transmitting power, orientation of transmitter and receiver, height of
transmitting antenna, height of receiving antenna, weather conditions, interference sources in the
area, and terrain between receiver and transmitter, including indoor and outdoor structures such as
walls, trees, buildings, hills, and mountains.
Specification XBee XBee-PRO
Indoor / urban range Up to 100 ft (30 m) Up to 300 ft (90 m) standard or up to 200 ft
(60 m) international variant
Outdoor RF line of
sight range
Transmit power
output
RF data rate 250 kb/s 250 kb/s
Serial interface data
rate (software
selectable)
Receiver sensitivity -92 dBm (1% packet error
Power requirements
The following table describes the power requirements for the XBee/XBee-PRO DigiMesh 2.4.
Specification XBee XBee-PRO
Supply voltage 2.8 - 3.4
Transmit current 45 mA (@
Up to 300 ft (90 m) Up to 1 mile (1.5 km), with a 2.0 dB dipole
antenna. Up to 6 miles (10 km) with a high
gain antenna.
1 mW (0 dBm) 63 mW (18 dBm) standard or 10 mW (10
dBm) for the international variant
1200 bps - 250 kb/s (devices
also support non-standard
baud rates)
rate)
2.8 - 3.4 VDC
VDC
250 mA (@ 3.3 V) (150 mA for the international variant)
3.3 V)
RPSMA device only: 340 mA (@ 3.3 V) (180 mA for the
international variant)
1200 bps - 250 kb/s (devices also support
non-standard baud rates)
-100 dBm (1% packet error rate)
Idle / receive current 50 mA (@
3.3 V)
Power down current (pin
sleep)
Power down current
(cyclic sleep)
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
<10 µA <10 µA
<50 µA <50 µA
55 mA (@ 3.3 V)
14
Technical specifications General specifications
General specifications
The following table describes the general specifications for the devices.
Specification XBee XBee-PRO
Operating frequency
band
Dimensions 2.438 cm x 2.761 cm (0.960 in x 1.087 in) 2.438 cm x 3.294 cm (0.960 in
Operatingtemperature -40 to 85 °C (industrial) -40 to 85 °C (industrial)
Relative humidity 0 to 95% non-condensing 0 to 95% non-condensing
Antenna options 1/4 wave wire antenna, embedded PCB
ISM 2.4 GHz ISM 2.4 GHz
antenna, RPSMA RF connector, U.FL RF
connector
Networking and security specifications
The following table describes the networking and security specifications for the devices.
Specification XBee XBee-PRO
Supported network
topologies
Number of channels
(software selectable)
Mesh, point-to-point, point-tomultipoint, peer-to-peer
16 direct sequence channels 12 direct sequence channels
x 1.297 in)
1/4 wave wire antenna,
RPSMA RF connector, U.FL RF
connector
Mesh, point-to-point, point-tomultipoint, peer-to-peer
Addressing options PAN ID, channel and 64-bit
addresses
Encryption 128 bit Advanced Encryption
Standard (AES)
Regulatory conformity summary
This table describes the agency approvals for the devices.
Specification XBee XBee-PRO
United States (FCC Part 15.247) OUR-XBEE OUR-XBEEPRO
Innovation, Science and Economic
Development Canada (ISED)
Europe (CE) Yes Yes (maximum 10 dBm transmit power
RoHS Lead-free and
4214A-XBEE 4214A-XBEEPRO
RoHS compliant
PAN ID, channel and 64-bit
addresses
128 bit AES
output)
Lead-free and RoHS compliant
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Technical specifications Regulatory conformity summary
Specification XBee XBee-PRO
Japan R201WW07215214 R201WW08215111 (maximum 10 dBm
transmit power output)
Australia C -Tick C -Tick
Brazil ANATEL 0369-15-
1209
See Regulatory information for region-specific certification requirements.
ANATEL 0378-15-1209
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Hardware
Mechanical drawings 18
Mounting considerations 19
Hardware diagram 20
Pin signals 21
Design notes 22
DC characteristics 25
ADC operating characteristics 25
ADC timing and performance characteristics 26
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Hardware Mechanical drawings
Mechanical drawings
The following figures show the mechanical drawings for the XBee/XBee-PRO DigiMesh 2.4. The
drawings do not show antenna options.
The following drawings show the RPSMA device.
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
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Hardware Mounting considerations
Mounting considerations
We design the through-hole module to mount into a receptacle so that you do not have to solder the
module when you mount it to a board. The development kits may contain RS-232 and USB interface
boards that use two 20-pin receptacles to receive modules.
The following illustration shows the module mounting into the receptacle on the RS-232 interface
board.
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Hardware Hardware diagram
n Through-hole single-row receptacles: Samtec part number: MMS-110-01-L-SV (or equivalent)
n Surface-mount double-row receptacles: Century Interconnect part number: CPRMSL20-D-0-1
(or equivalent)
n Surface-mount single-row receptacles: Samtec part number: SMM-110-02-SM-S
Note We recommend that you print an outline of the module on the board to indicate the
correct orientation for mounting the module.
Hardware diagram
The following diagram shows a simplified view of XBee/XBee-PRO DigiMesh 2.4 hardware.
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
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Hardware Pin signals
Pin signals
The following table shows the pin signals and their descriptions.
Pin
# Pin name Direction Description
1 Vcc - Power supply
2 DOUT Output UART data out
3 DIN/CONFIG Input UART data in
4 DIO12 Either Digital I/O 12
5 RESET Input/open
drain
output
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
8 Reserved - Do not connect
DTR/SLEEP_
9
RQ/DIO8
10 GND - Ground
11 AD4/ DIO4 Either Analog input 4 or Digital I/O 4
CTS/ DIO7
12
13 ON/SLEEP Output Device Status Indicator or Digital I/O 9
14 VREF - You must connect this line if you want to use analog I/O
Either Pin sleep control line or Digital I/O 8
Either Clear-to-send flow control or Digital I/O 7
Device reset. The reset pulse must be at least 100 µs.
Drive this line as an open drain/collector. The device
drives this line low when a reset occurs. Never drive this
line high.
sampling. Must be between 2.6 V and Vcc.
15 Associate/DIO5/AD5 Either Associated indicator, Digital I/O 5
RTS/ DIO6
16
17 AD3 / DIO3 Either Analog input 3 or Digital I/O 3
18 AD2 / DIO2 Either Analog input 2 or Digital I/O 2
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
Either Request-to-send flow control, Digital I/O 6
21
Hardware Design notes
Pin
# Pin name Direction Description
19 AD1 / DIO1 Either Analog input 1 or Digital I/O 1
20 AD0 / DIO0 /
Commissioning
Pushbutton
Either Analog input 0, Digital I/O 0, or Commissioning
Pushbutton
Notes
The table specifies signal direction with respect to the device.
The device includes a 50 kΩ pull-up resistor attached to RESET.
You can configure several of the input pull-ups using the PR command.
Leave any unused pins disconnected.
Recommended pin connections
The only required pin connections for two-way communication are VCC, GND, DOUT and DIN. To
support serial firmware updates, you must connect VCC, GND, DOUT, DIN, RTS, and DTR.
Do not connect any pins that are not in use. Use the PR command to pull all inputs on the radio high
with internal pull-up resistors. Unused outputs do not require any specific treatment.
For applications that need to ensure the lowest sleep current, never leave unconnected inputs
floating. Use internal or external pull-up or pull-down resistors, or set the unused I/O lines to outputs.
You can connect other pins to external circuitry for convenience of operation including the Associate
LED pin (pin 15) and the Commissioning pin (pin 20). The Associate LED pin flashes differently
depending on the state of the module, and a pushbutton attached to pin 20 can enable various
deployment and troubleshooting functions without you sending UART commands. For more
information, see The Commissioning Pushbutton.
For analog sampling, attach the VREF pin (pin 14) to a voltage reference.
Design notes
The following guidelines help to ensure a robust design.
Power supply design
A poor power supply can lead to poor device performance, especially if you do not keep the supply
voltage within tolerance or if it is excessively noisy. To help reduce noise, place a 1.0 μF and 8.2 pF
capacitor as near as possible to pin 1 on the PCB. If you are using a switching regulator for the power
supply, switch the frequencies above 500 kHz. Limit the power supply ripple to a maximum 100 mV
peak to peak.
Board layout
We design XBee devices to be self sufficient and have minimal sensitivity to nearby processors,
crystals or other printed circuit board (PCB) components. Keep power and ground traces thicker than
signal traces and make sure that they are able to comfortably support the maximum current
specifications. There are no other special PCB design considerations to integrate XBee devices, with
the exception of antennas.
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
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Hardware Design notes
Antenna performance
Antenna location is important for optimal performance. The following suggestions help you achieve
optimal antenna performance. Point the antenna up vertically (upright). Antennas radiate and receive
the best signal perpendicular to the direction they point, so a vertical antenna's omnidirectional
radiation pattern is strongest across the horizon.
Position the 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:
n metal poles
n metal studs
n structure beams
n concrete, which is usually reinforced with metal rods
If you place the device inside a metal enclosure, use an external antenna. Common objects that have
metal enclosures include:
n vehicles
n elevators
n ventilation ducts
n refrigerators
n microwave ovens
n batteries
n tall electrolytic capacitors
Do not place XBee devices with the chip or integrated PCB antenna inside a metal enclosure.
Do not place any ground planes or metal objects above or below the antenna.
For the best results, mount the device at the edge of the host PCB. Ensure that the ground, power,
and signal planes are vacant immediately below the antenna section.
Keepout area
We recommend that you allow a “keepout” area, as shown in the following drawing.
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
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Hardware Design notes
Through-hole keepout
Notes
1. We recommend non-metal enclosures. For metal enclosures, use an external antenna.
2. Keep metal chassis or mounting structures in the keepout area at least 2.54 cm (1 in) from the
antenna.
3. Maximize the distance between the antenna and metal objects that might be mounted in the
keepout area.
4. These keepout area guidelines do not apply for wire whip antennas or external RFconnectors.
Wire whip antennas radiate best over the center of a ground plane.
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
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Hardware DC characteristics
DC characteristics
The following table displays the DC characteristics (VCC = 2.8 - 3.4 VDC).
Symbols Parameter Condition Min Typical Max Units
VCC
VCC
1
V
3
V
V
IL
V
IH
Input low voltage All digital inputs - - 0.2
Input high voltage All digital inputs 0.8
2
- - V
VCC
V
OL
Output low
IOL= 2 mA, VCC >= 3.0 V - - 0.18
voltage
VCC
4
- - V
V
OH
Output high
IOH= 2 mA, VCC >= 3.0 V 0.82
voltage
II
IN
Input leakage
current
VIN= VCC or GND, all inputs,
per pin
ADC operating characteristics
The following table displays the ADC timing and performance characteristics.
Symbols Parameter Condition Min Typical Max Units
V
I
V
REF
REFH
INDC
VREF-analog-to-digital converter
reference range
VREF-reference supply current Enabled - 200 - μA
5
Analog input voltage V
Disabled or
sleep mode
- - 0.5 μA
2.08 - V
DDAD
V
- < 0.01 0.02 μA
-
SSAD
0.3
- V
SSAD
0.3
+
V
1
Maximum electrical operating range, not valid conversion range.
2
Maximum electrical operating range, not valid conversion range.
3
Maximum electrical operating range, not valid conversion range.
4
Maximum electrical operating range, not valid conversion range.
5
Analog input must be between V
$3FF.
REFL
and V
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
for valid conversion. Values greater than V
REFH
will convert to
REFH
25
Hardware ADC timing and performance characteristics
ADC timing and performance characteristics
The following table displays the ADC timing and performance characteristics.
Symbols Parameter Condition Min Typical Max Units
R
AS
Source impedance at input
2
- - 10 kΩ
1
RES
Ideal resolution (1 LSB)
DNL Differential non-linearity
INL Integral non-linearity
E
ZS
F
FS
E
IL
E
TU
1
All Accuracy numbers are based on processor and system being in WAIT state (very little activity and no I/O
switching) and that adequate low-pass filtering is present on analog input pins (filter with 0.01 µF to 0.1 µF
capacitor between analog input and V
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
The resolution is the ideal step size or 1LSB = (V
4
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.
5
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/
((V
REFH+EFS
6
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/(V
7
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/(V
8
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.
9
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 (1/2 LSB) and circuit
error (differential, integral, zero-scale, and full-scale) error. The specified value of ETUassumes zero EIL(no
leakage or zero real source impedance).
Zero-scale error
Full-scale error
7
Input leakage error
Total unadjusted error
).(V
REFL+EZS
))).
3
4
5
6
2.08V > V
> 3.6V 2.031 3.516 mV
DDAD
- ±0.5 ±1.0 LSB
- ±0.5 ±1.0 LSB
- ±0.4 ±1.0 LSB
- ±0.4 ±1.0 LSB
8
9
). Failure to observe these guidelines may result in system or
REFL
REFH–VREFL
)/1024.
- ±0.05 ±5.0 LSB
- ±1.1 ±2.5 LSB
REFH·VREFL
REFH·VREFL
)).
)).
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
26
Modes
The XBee/XBee-PRO DigiMesh 2.4 is in Receive Mode when it is not transmitting data. The device
shifts into the other modes of operation under the following conditions:
n Transmit mode (Serial data in the serial receive buffer is ready to be packetized)
n Sleep mode
n Command Mode (Command mode sequence is issued (not available when using the SPI port))
Transparent and API operating modes 28
Additional modes 30
Command mode 31
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
27
Modes Transparent and API operating modes
Transparent and API operating modes
The firmware operates in several different modes. Two top-level modes establish how the device
communicates with other devices through its serial interface: Transparent operating mode and API
operating mode.
Transparent operating mode
Devices operate in this mode by default. The device acts as a serial line replacement when it is in
Transparent operating mode. The device queues all UART data it receives through the DIN pin for RF
transmission. When a device receives RF data, it sends the data out through the DOUT pin.
API operating mode
API operating mode is an alternative to Transparent operating mode. API mode is a frame-based
protocol that allows you to direct data on a packet basis. The device communicates UART data in
packets, also known as API frames. This mode allows for structured communications with computers
and microcontrollers.
The advantages of APIoperating mode include:
n It is easier to send information to multiple destinations
n The host receives the source address for each received data frame
n You can change parameters without entering Command mode
n You can query or set a configuration parameter while a pending command—for example ND—is
in progress. This cannot be done in Command mode.
For more information, see API frame specifications.
Comparing Transparent and API modes
The XBee/XBee-PRO DigiMesh 2.4 can use its serial connection in two ways:Transparent mode or API
operating mode. You can use a mixture of devices running API mode and transparent mode in a
network.
The following table provides a comparison of the two modes.
Transparent operating mode API operating mode
When to use:
n The conditions for using API mode
do not apply.
When to use:
n The device sends wireless data to multiple
destinations.
n The device configures remote devices in the
network.
n The device receives wireless data packets from
multiple XBee devices, and the application needs
to identify which devices send each packet.
n The device receives I/O samples from remote
XBee devices.
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
28
Modes Transparent and API operating modes
Transparent operating mode API operating mode
Advantages:
n Provides a simple interface.
n It is easy for an application to
support; what you send is exactly
what other modules get, and vice
versa.
n Works very well for two-way
communication between XBee
devices.
Disadvantages:
n You cannot set or read the
configuration of remote XBee
devices in the network.
n You must first update the
configuration to establish a new
destination and transmit data.
n You cannot identify the source of
received data, as it does not
include the sender's address.
n Received data does not include
transmission details or the
reasons for success or failure.
n This mode does not offer the
advanced features of API mode,
including advanced networking
diagnostics, and firmware
upgrades.
Advantages:
n You can set or read the configuration of remote
XBee devices in the network.
n You can transmit data to one or multiple
destinations; this is much faster than
Transparent mode where the configuration must
be updated to establish a new destination.
n Received data includes the sender's address.
n Received data includes transmission details and
reasons for success or failure.
n This mode has several advanced features, such
as advanced networking diagnostics, and
firmware upgrades.
Disadvantages:
n The interface is more complex; data is
structured in packets with a specific format.
n This mode is more difficult to support;
transmissions are structured in packets that
need to be parsed (to get data) or created (to
transmit data).
n Sent data and received data are not identical;
received packets include some control data and
XTend vB information.
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
29
Modes Additional modes
Additional modes
In addition to the serial communication modes, several modes apply to how devices communicate
with each other.
Command mode
Command mode is a state in which the firmware interprets incoming characters as commands.
Command mode allows you to modify the device’s firmware using parameters you can set using AT
commands. When you want to read or set any setting of the device, you have to send it an AT
command. Every AT command starts with the letters "AT", followed by the two characters that
identify the command that is being sent and then by some optional configuration values. For more
details, see Enter Command mode.
Idle mode
The device is in Idle mode when it is not receiving or transmitting data. During Idle mode, the device
listens for valid data on both the RF and serial ports.
Receive mode
If a destination node receives a valid RF packet, the destination node transfers the data to its serial
transmit buffer. For the serial interface to report receive data on the RF network, that data must
meet the following criteria:
n ID match
n Channel match
n Address match
Sleep modes
Sleep modes allows the device to enter states of low power consumption when not in use. The device
is almost completely off during sleep, and is incapable of sending or receiving data until it wakes up.
XBee devices support both pin sleep, where the module enters sleep mode upon pin transition, and
cyclic sleep, where the module sleeps for a fixed time. While asleep, nodes cannot receive RF
messages or read commands from the UART port.
The sleep modes are:
n Normal mode. Normal mode is the default for a newly powered-on node. In this mode, a node
does not sleep. Normal mode nodes should be mains-powered.
n Asynchronous Pin Sleep mode. This mode allows the device to sleep and wake according to the
state of the Sleep_RQ pin (pin 9).
n Asynchronous Cyclic Sleep Mode. This mode allows the device to sleep for a specified time and
wake for a short time to poll.
n Asynchronous Cyclic Sleep with Pin Wake Up mode. In this mode you can wake the device up
prematurely using the Sleep_RQ pin.
n Synchronous Sleep Support mode. A node in this mode synchronizes itself with a sleeping
network, but does not sleep itself. At any time, the node responds to new nodes that attempt
to join the sleeping network using a sync message.
XBee/XBee-PRO DigiMesh 2.4 RF Module User Guide
30
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