Digi 9XTENDB XTend RF module User Manual product manual XTend OEM RF Module v2 x4x

Digi International Inc XTend RF module product manual XTend OEM RF Module v2 x4x

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User Manual

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XTend™ RF Module
Firmware versions supported in this
manual:
Standard firmware: 2x6x
For DigiMesh version refer to XTend
DigiMesh manual (90002166_A)
Digi International Inc.
11001 Bren Road East
Minnetonka, MN 55343
877 912-3444 or 952 912-3444
http://www.digi.com
90000958_E
2012.09.7
XTend™ RF Module - Product Manual
© 2012 Digi International, Inc. All rights reserved
The contents of this manual may not be transmitted or reproduced in any form or
by any means without the written permission of Digi International, Inc..
XTend™ is a trademark of Digi International, Inc.
AES Encryption Source Code
© 2012 Dr. Brian Gladman, Worcester, UK. All rights reserved.
Conditions:
- Distributions of AES source code include the above copyright notice, this list of
conditions and disclaimer.
- Distributions in binary form include the above copyright notice, this list of conditions and disclaimer in the documentation and/or other associated materials.
- The copyright holder's name is not used to endorse products built using this
software without specific written permission.
Alternatively, provided that this notice is retained in full, this product may be distributed under the terms of the GNU General Public License (GPL), in which case
the provisions of the GPL apply INSTEAD OF those given above.
Disclaimer - This AES software is provided 'as is' with no explicit or implied warranties in respect of its properties, including, but not limited to, correctness and/or
fitness for purpose.
Technical Support:
Phone: (801) 765-9885
Live Chat: www.digi.com
E-support: http://www.digi.com/support/eservice/eservicelogin.jsp
© 2012 Digi International, Inc.
ii
XTend™ RF Module – Product Manual
Contents
1. XTend RF Module
Polling Mode (Acknowledged) 53
5. Appendix A: Agency Certifications
Key Features 4
Worldwide Acceptance 4
FCC (United States) Certification 55
Specifications 5
Integrator Labeling Requirements 55
Pin Signals 6
FCC Notices 55
Electrical Characteristic 7
Limited Modular Approval 56
Timing Specifications 7
FCC-approved Antennas 56
Mechanical Drawings 9
2. RF Module Operation
IC (Industry Canada) Certification 60
10
Labeling Requirements 60
Transmitters for Detachable Antennas 60
Serial Communications 10
Detachable Antennas 61
UART Data Flow 10
C-TICK (Australia) Certification 61
Flow Control 11
Power Requirements 61
Transparent Operation 12
6. Appendix B: Development Guide
API Operation 12
DigiMesh Operation 12
62
Development Kit Contents 62
Modes of Operation 13
Interfacing Hardware 62
Idle Mode 13
XTIB-R RS-232/485 Interface Board 63
Transmit Mode 13
Automatic DIP Switch Configurations 64
Receive Mode 14
Adapters 65
Shutdown Mode 15
Interfacing Protocols 67
Sleep Mode 15
RS-232 Operation 67
Command Mode 17
3. RF Module Configuration
55
RS-485 (2-wire) Operation 69
20
RS-485 (4-wire) & RS-422 Operation 70
X-CTU Software 72
Programming Examples 20
Installation 72
AT Commands 20
Serial Communications Software 72
Binary Commands 20
7. Appendix C: Additional Information
Command Reference Table 21
Command Descriptions 23
1-Year Warranty 73
API Operation 41
Contact Digi 74
73
API Frame Specifications 41
API Types 42
4. RF Communication Modes
44
Addressing 45
Address Recognition 45
Basic Communications 46
Streaming Mode (Default) 46
Multi-transmit Mode 47
Repeater Mode 48
Polling Mode (Basic) 51
Acknowledged Communications 52
Acknowledged Mode 52
© 2012 Digi International, Inc.
iii
1. XTend RF Module
The XTend RF Module was engineered to provide customers with an
easy-to-use RF solution that provides reliable delivery of critical
data between remote devices. The module transfers a standard
asynchronous serial data stream, operates within the ISM 900 MHz
frequency band and sustains up to 115.2 Kbps data throughput.
Key Features
Long Range Data Integrity
Low Power
1 Watt Power Output (variable 1mW - 1W)
2.8 - 5.5 V Supply Voltage
Range (@9,600 bps throughput data rate):
Pin, Serial Port and Cyclic
software sleep modes supported
• Indoor/Urban: up to 3000’ (900 m)
• Outdoor RF line-of-sight:
up to 14 miles (22 km) w/dipole antenna
• Outdoor RF line-of-sight:
up to 40 miles (64 km) w/high-gain antenna
Range (@115,200 bps throughput data rate):
• Indoor/Urban: up to 1500’ (450 m)
• Outdoor RF line-of-sight:
up to 7 miles (11 km) w/dipole antenna
• Outdoor RF line-of-sight:
up to 20 miles (32 km) w/high-gain antenna
Continuous RF data stream up to 115,200 bps
Receiver Sensitivity: -110 dBm (@ 9600 baud),
–100 dBm (@ 115200 baud)
Advanced Networking & Security
Shutdown pin enables hardware sleep mode
that draws only 5 µA (typical)
Easy-to-Use
No configuration necessary for out-of box
RF communications
Free X-CTU Software
(Testing and configuration software)
RF Modules easily configured using
standard AT & binary commands
Transparent Operation
(Wireless links replace serial wires)
API Operation
(Frame-based communications)
True Peer-to-Peer (no Master device required),
Point-to-Point, Point-to-Multipoint & Multidrop
Portable
(small form-factor easily designed into
a wide range of data systems)
Retries and Acknowledgements
Software-selectable I/O interfacing rates
FHSS (Frequency Hopping Spread Spectrum)
Multiple data formats supported
(parity, start and stop bits, etc.)
10 hopping channels, each with over 65,000
unique network addresses available
256-bit AES Encryption
- performed using a FIPS 197 certified
implementation on a Phillips LPC microcontroller
XII™ Interference Immunity
No Master/Slave setup dependencies
128-bit AES for international variant
Worldwide Acceptance
FCC Approved (USA) Refer to Appendix A [p55] for FCC Requirements.
Systems that include XTend RF Modules inherit Digi’s Certifications.
ISM (Industrial, Scientific & Medical) license-free 902-928 MHz frequency band
Manufactured under ISO 9001:2000 registered standards
ESD (Electrostatic Discharge) immunity - ESD-hardened and IEC1000-4-2 (Level 4) tested
© 2012 Digi International Inc.
XTend™ RF Module - Product Manual
XTend RF Modules are optimized for use in the US, Canada, and Australia
(contact Digi for complete list of agency approvals).
Specifications
Table 1-01.
XTend RF Module
XTend 900 MHz RF Module Specifications
Performance
Transmit Power Output
(software selectable using PL command)
Indoor/Urban Range
@9600 bps Throughput Data Rate
@115200 bps Throughput Data Rate
1mW - 1 Watt
1mW - 1 Watt
Up to 3000’ (900 m)
Up to 1500’ (450 m)
Up to 14 miles (22 km) w/ dipole antenna
Up to 40 miles (64 km) w/ high-gain antenna
Up to 7 miles (11 km) w/ dipole antenna
Up to 20 miles (32 km) w/ high-gain antenna
Interface Data Rate
(software selectable using BD command)
1200 – 230400 bps
1200 – 230400 bps
Throughput Data Rate
(software selectable using BR command)
9,600 bps
115,200 bps
RF Data Rate
10,000 bps
125,000 bps
Receiver Sensitivity
-110 dBm
-100 dBm
Outdoor
RF line-of-sight Range
Power Requirements
Receive Current
80 mA
Shutdown Mode Power Down
Pin Sleep Power Down
16 sec cyclic sleep (SM=8)
Idle Currents
5 µA typical
162 µA
0.3 - 0.8 mA
8 sec cyclic sleep (SM=7)
0.4 - 1.4 mA
4 sec cyclic sleep (SM=6)
0.6 - 2.6 mA
2 sec cyclic sleep (SM=5)
0.9 - 4.8 mA
1 sec cyclic sleep (SM=4)
1.6 - 8.7 mA
Networking & Security
Frequency
Spread Spectrum
Modulation
Supported Network Topologies
Channel Capacity
Encryption
902-928 MHz, 915-928 MHz International variant
FHSS (Frequency Hopping Spread Spectrum)
FSK (Frequency Shift Keying)
Peer-to-Peer (“Master/Slave” relationship not required), Point-to-Point, Point-to-Multipoint, Mesh
10 hop sequences share 50 frequencies
256-bit or 128-bit AES Encryption – Refer to the KY Command [p29] to implement
Physical Properties
RF Module Board Size
Weight
Connector
Operating Temperature
1.44” x 2.38” x 0.20” (3.65 cm x 6.05 cm x 0.51 cm)
0.64 oz. (18 g)
20-pin
-40 to 85º C (industrial)
Antenna
Connector Options
Impedance
RPSMA (Reverse-polarity SMA) or MMCX
50 ohms unbalanced
Certifications (partial list)
FCC Part 15.247
MCQ-9XTENDB
Industry Canada (IC)
1846A-9XTENDB
© 2012 Digi Internatonal, Inc.
XTend™ RF Module - Product Manual
Table 1-02.
XTend RF Module Specifications - Relative to user-selected TX Power Output
Power Requirements (Supply voltage and TX currents relative to each TX Power Output option)
Transmit Power Output
1 mW
Supply Voltage
10 mW
100 mW
2.8 - 5.5 VDC
500 mW *
1W*
3.0 - 5.5 VDC
4.75 - 5.5 VDC
Transmit Current (5 V) typical
130 mA
160 mA
270 mA
500 mA
680 mA
Transmit Current (3.3 V) typical
125 mA
150 mA
260 mA
600 mA
**
* If the supply voltage for a given power setting is lower than the minimum supply voltage requirement (as shown in Table 1-02), the
TX Power Output will decrease to the highest power level setting given the current supply voltage.
** 1W Power Output is not supported when using a 3.3 supply voltage.
Pin Signals
Figure 1-01. XTend RF Module Pin Numbers
Table 1-03.
Pin Signal Descriptions
(Low-asserted signals distinguished with a horizontal line over signal name.)
Pin
Number
Mnemonic
I/O
High Impedance
during Shutdown
Must
Connect
GND
yes
Ground
VCC
yes
Power: 2.8 - 5.5 VDC (Power supply ripple: +/- 250mV max @ 5V, 1A or +/125mV max @ 3.3V, 600mA.)
GPO2 /
RX LED
yes
TX_PWR
yes
DI
yes
yes
Data In: Serial data entering the module (from the UART host). Refer to the Serial
Communications [p10] section for more information.
DO
yes
Data Out: Serial Data exiting the module (to the UART host). Refer to the Serial
Communications [p10] section for more information.
SHDN
no
yes
Shutdown: Pin is driven high during operation and low during Shutdown.
Shutdown enables the lowest power mode (~5 µA) available to the module. Refer
to the Shutdown Mode [p15] section for more information.
Function
General Purpose Output 2:  Pin is driven low. Refer to the CD
Command [p25] for other configuration options.
RX LED: Pin is driven high during RF data reception; otherwise, the pin is driven
low. Refer to the CD Command [p25] to enable.
Transmit_Power: Pin pulses low during RF transmission; otherwise, the pin is
driven high to indicate power is on and the module is not in Sleep or Shutdown
Mode.
General Purpose Input 2: reserved for future use
GPI2 / SLEEP
yes
SLEEP: By default, SLEEP is not used. To configure this pin to enable Sleep
Modes, refer to the Sleep Mode [p15], SM Command [p37] & PW Command [p32]
sections.
General Purpose Output 1: reserved for future use
GPO1 / CTS /
RS-485 TX_EN
yes
CTS (Clear-to-Send):  When pin is driven low, the UART host
is permitted to send serial data to the module. Refer to the Serial Communications
[p10] & CS Command [p25] sections for more information.
RS-485 Transmit Enable: To configure this pin to enable RS-485 half and fullduplex communications. Refer to the Serial Communications [p10] & CS
Command [p25] sections.
General Purpose Input 1: reserved for future use
10
GPI1 / RTS /
CMD
yes
RTS (Request-to-Send): By default, is not used. To configure this pin to
regulate the flow of serial data exiting the module, refer to the Serial
Communications [p10] & RT Command [p36] sections.
CMD (Command): By default, CMD is not used. To configure this pin to enable
binary command programming, refer to the Binary Commands [p18] & RT
Command [p36] sections.
© 2012 Digi Internatonal, Inc.
XTend™ RF Module - Product Manual
Table 1-03.
Pin
Number
11
Pin Signal Descriptions
(Low-asserted signals distinguished with a horizontal line over signal name.)
Mnemonic
I/O
High Impedance
during Shutdown
Must
Connect
I*
no
Configuration: Pin can be used as a backup method for entering Command
Mode during power-up. Refer to the Command Mode [p17] section for more
information.
O*
no
Receive Signal Strength Indicator: By default, pin is used as an RSSI PWM
output after at the conclusion of the power-up sequence. Refer to the RP
Command [p35] for more information. The PWM output is 2.8V-level.
CONFIG / RSSI
12-20
Function
reserved / do not connect
* RF module has 10K Ω internal pull-up resistor
Note: When integrating the module with a Host PC board, all lines not used should be left disconnected (floating).
Electrical Characteristic
Figure 1-02. System Block Diagram
Basic RF Link between Hosts
The data flow sequence is initiated when the first byte of data is received in the DI Buffer of the
transmitting module (XTend RF Module A). As long as XTend RF Module A is not already receiving
RF data, data in the DI Buffer is packetized then transmitted over-the-air to XTend RF Module B.
Timing Specifications
Figure 1-03. Timing Specifications (‘A’ and ‘B’ refer to Figure 1-02)
© 2012 Digi Internatonal, Inc.
XTend™ RF Module - Product Manual
Table 1-04.
AC Characteristics (Symbols correspond with Figure 1-02 and Figure 1-03, ATSY Parameter = 0)
Symbol
TTX
Description
Latency from the time data is
transmitted until it is received.
Sleep Mode
115200 Baud Rate
9600 Baud Rate
SM = 0
(No sleep)
9.4 msec
94 msec
SM = 8
16 sec
16 sec
SM = 7
8 sec
8 sec
SM = 6
4 sec
4 sec
SM = 5
2 sec
2 sec
SM = 4
1 sec
1 sec
TTL
Time that TX_PWR pin (pin 4) is driven
low
--
2.45 msec
29.6 msec
TRL
Time that RX LED (pin 3)
is driven high
--
2.26 msec
27.2 msec
TCLDL
Time starting when CTS goes low until
the first bit appears on DOUT
--
44 µsec
75 µsec
TCHDH
Time after last bit of data until
CTS goes high
--
7 µsec
7 µsec
Table 1-05.
DC Characteristics (Vcc = 2.8 - 5.5 VDC)
Symbol
Parameter
Condition
VOL
Output Low Voltage
VOL = 0.33V (IO = 6 mA)
VOH
Output High Voltage
VOH = VSUPPLY - 0.7V (-IO = 6 mA)
Figure 1-04. Input Thresholds vs. Supply Voltage
Input thresholds vs. supply voltage
2.5
I/O Voltage
1.5
V(IL)
V(IH)
0.5
2.5
3.5
4.5
5.5
Vcc
© 2012 Digi Internatonal, Inc.
XTend™ RF Module - Product Manual
Mechanical Drawings
Figure 1-05. Mechanical drawings of the XTend RF Module (w/RPSMA Connector)
Figure 1-06. Mechanical drawings of the XTend RF Module (w/MMCX Connector)
© 2012 Digi Internatonal, Inc.
2. RF Module Operation
WARNING: When operating at 1 Watt power output, observe a minimum separation distance of 2' (0.6m) between
modules. Transmitting in close proximity of other modules can damage module front ends.
Serial Communications
The XTend RF Modules interface to a host device through a TTL-level asynchronous serial port.
Through its serial port, the module can communicate with any UART voltage compatible device or
through a level translator to any serial device (For example: RS-232/485/422 or USB interface
board).
UART Data Flow
Devices that have a UART interface can connect directly to the pins of the RF module as shown in
the figure below.
Figure 2-01. System Data Flow Diagram in a UART-interfaced environment
(Low-asserted signals distinguished with horizontal line over signal name.)
Serial Data
Data enters the module UART through the pin 5 as an asynchronous serial signal. The signal
should 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.
Figure 2-02. UART data packet 0x1F (decimal number "31") as transmitted through the RF module
Example Data Format is 8-N-1 (bits - parity - # of stop bits)
The module UART performs tasks, such as timing and parity checking, that are 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).
© 2012 Digi International Inc.
10
XTend™ RF Module - Product Manual
Flow Control
Figure 2-03. Internal Data Flow Diagram (The five most commonly-used pin signals shown)
DI (Data In) Buffer and Flow Control
When serial data enters the module through the DI pin (pin 5), the data is stored in the DI Buffer
until it can be processed.
When the RB and RO parameter thresholds are satisfied (refer to ‘Transmit Mode’ section for more
information), the module attempts to initialize an RF connection. If the module is already receiving
RF data, the serial data is stored in the module's DI Buffer. The DI buffer stores at least 2.1 KB. If
the DI buffer becomes full, hardware or software flow control must be implemented in order to
prevent overflow (loss of data between the host and RF module).
How to eliminate the need for flow control:
1.
Send messages that are smaller than the DI buffer size. The size of the DI buffer varies
according to the packet size (PK parameter) and the parity setting (NB parameter) used.
2.
Interface at a lower baud rate (BD parameter) than the RF data rate (BR parameter).
Two cases in which the DI Buffer may become full and possibly overflow:
1.
If the serial interface data rate is set higher than the RF data rate of the module, the module will receive data from the host faster than it can transmit the data over-the-air.
2.
If the module is receiving a continuous stream of RF data or if the module is monitoring
data on a network, any serial data that arrives on the DI pin (pin 5) is placed in the DI Buffer. The data in the DI buffer will be transmitted over-the-air when the module no longer
detects RF data in the network.
Hardware Flow Control (CTS). When the DI buffer is 17 bytes away from being full; by default,
the module de-asserts CTS (high) to signal to the host device to stop sending data [refer to FT
(Flow Control Threshold) and CS (GPO1 Configuration) Commands]. CTS is re-asserted after the
DI Buffer has 34 bytes of memory available.
Software Flow Control (XON). XON/XOFF software flow control can be enabled using the FL
(Software Flow Control) Command. This option only works with ASCII data.
DO (Data Out) Buffer
When RF data is received, the data enters the DO buffer and is sent out the serial port to a host
device. Once the DO Buffer reaches capacity, any additional incoming RF data is lost. The DO
buffer stores at least 2.1 KB.
Two cases in which the DO Buffer may become full and possibly overflow:
1.
If the RF data rate is set higher than the interface data rate of the module, the module will
receive data from the transmitting module faster than it can send the data to the host.
2.
If the host does not allow the module to transmit data out from the DO buffer because of
being held off by hardware or software flow control.
Hardware Flow Control (RTS). If RTS is enabled for flow control (RT Parameter = 2), data will
not be sent out the DO Buffer as long as RTS (pin 10) is de-asserted.
Software Flow Control (XOFF). XON/XOFF software flow control can be enabled using the FL
(Software Flow Control) Command. This option only works with ASCII data.
© 2012 Digi Internatonal, Inc.
11
XTend™ RF Module - Product Manual
Transparent Operation
By default, XTend RF Modules operate in Transparent Mode. The modules act as a serial line
replacement - all UART data received through the DI pin is queued up for RF transmission. When
RF data is received, the data is sent out the DO pin.
When the RO (Packetization Timeout) parameter threshold is satisfied, the module attempts to
initialize an RF transmission. If the module cannot immediately transmit (for instance, if it is
already receiving RF data), the serial data continues to be stored in the DI Buffer. Data is
packetized and sent at any RO timeout or when the maximum packet size is received.
The module operates as described above unless the Command Mode Sequence is detected. The
Command Mode Sequence consists of three copies of the command sequence character [CC
parameter] surrounded by the before and after guard times [BT & AT parameters].
If the DI buffer becomes full, hardware or software flow control must be implemented in order to
prevent overflow (loss of data between the host and module).
API Operation
API (Application Programming Interface) Operation is an alternative to the default Transparent
Operation. The API is frame-based and extends the level to which a host application can interact
with the networking capabilities of the module. When in API mode, all data entering and leaving
the RF module is contained in frames that define operations or events within the module.
Transmit Data Frames (received through the DI (Data In) pin) include:
• 16-bit address
Receive Data Frames (sent out the DO (Data Out) pin) include:
• Showing a received RF packet (16 bits only)
• Response to a TX (Transmit) packet
• Showing events such as hardware reset, watchdog reset, asynchronous events, etc.
The module will send data frames to the application containing status packets; as well as source,
RSSI and payload information from received data packets.
API operation option facilitates many operations such as the examples cited below:
-> Change destination addresses without having to enter command mode
-> Receive success/failure status of each RF packet
-> Identify the source address of each received packet
To implement API operations, refer to ‘API Operation’ sections [p40].
DigiMesh Operation
XTend RF Modules containing firmware version 8020 (or above) now feature DigiMesh mesh
networking support. Mesh networking allows messages to be routed through several different
XTend nodes to a final destination node. This firmware load allows system integrators to bolster
their networks with the self-healing attributes of mesh networking. In the event that one RF
connection between nodes is lost (due to power-loss, environmental obstructions, etc.) critical
data can still reach its destination due to mesh networking capabilities embedded inside the
module. Transparent or API operations can be used in conjunction with the mesh networking
topology. A separate product manual exists for DigiMesh modules. This product manual can be
found on the Digi support site.
© 2012 Digi Internatonal, Inc.
12
XTend™ RF Module - Product Manual
Modes of Operation
XTend RF Modules operate in six modes.
Figure 2-04. XTend RF Module Modes of Operation
(RF modules can only be in one mode at a time)
Idle Mode
When not receiving or transmitting data, the RF module is in Idle Mode. The module shifts into the
other modes of operation under the following conditions:
• Transmit Mode: Serial data is received in the DI Buffer
• Receive Mode: Valid RF data is received through the antenna
• Shutdown Mode: Shutdown condition is met
• Sleep Mode: Sleep Mode condition is met
• Command Mode: Command Mode Sequence is issued
The module automatically transitions back to Idle Mode after responding to these conditions.
Transmit Mode
When the first byte of serial data is received from the UART in the DI buffer, the module attempts
to shift to Transmit Mode and initiate an RF connection with other modules. After transmission is
complete, the module returns to Idle Mode.
RF transmission begins after either of the following criteria is met:
1.
RB bytes have been received by the UART and are pending for RF transmission.
[Refer to the RB (Packetization Threshold) Command]
2.
At least one character has been received by the UART and is pending for RF transmission;
and RO character times of silence been observed on the UART.
[Refer to the RO (Packetization Timeout) Command]
Figure 2-05. Transmit Mode Data Flow
The character timeout trigger can be
disabled by setting RO to zero. In this
case, transmission will not begin until
RB bytes have been received and are
pending for RF transmission. The RB
parameter may be set to any value
between 1 and the RF packet size [refer
to PK (Max RF Packet Size) parameter],
inclusive. Note that transition to
Transmit Mode cannot take place during
RF reception; the RF reception must
complete before the radio can transition
into Transmit Mode.
If RB or RO conditions are met, the
module initializes a communications channel. Serial data in the DI buffer is grouped into RF
packets (up to 2048 bytes in each packet, refer to PK Command), converted to RF data and is
transmitted over-the-air until the DI buffer is empty.
© 2012 Digi Internatonal, Inc.
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XTend™ RF Module - Product Manual
Channel initialization is the process of sending an RF initializer that synchronizes receiving
modules with the transmitting module. During channel initialization, incoming serial data
accumulates in the DI buffer.
RF data, which includes the payload data, follows the RF initializer. The payload includes up to the
maximum packet size (PK Command) bytes. As the TX module nears the end of the transmission,
it inspects the DI buffer to see if more data exists to be transmitted. This could be the case if more
than PK bytes were originally pending in the DI buffer or if more bytes arrived from the UART after
the transmission began. If more data is pending, the transmitting module assembles a subsequent
packet for transmission.
Refer to the ‘RF Communication Modes’ section to view state diagrams that illustrate channel
initialization and the sequence of events that follow.
RF Packet
Figure 2-06. RF Packet Components
* When streaming multiple RF packets, the RF Initializer is only sent in front of the first packet.
RF Initializer
An RF initializer is sent each time a new connection sequence begins. The RF initializer contains
channel information that notifies receiving modules of information such as the hopping pattern
used by the transmitting module. The first transmission always sends an RF initializer.
An RF initializer can be of various lengths depending on the amount of time determined to be
required to prepare a receiving module. For example, a wake-up initializer is a type of RF initializer
used to wake remote modules from Sleep Mode (Refer to the FH, LH, HT and SM Commands for
more information). The length of the wake-up initializer should be longer than the length of time
remote modules are in cyclic sleep.
Header
The header contains network addressing information that filters incoming RF data. The receiving
module checks for matching a Hopping Channel, VID and Destination Address. Data that does not
pass through all three network filter layers is discarded.
Refer to the ‘Addressing’ section of the “RF Communication Modes” chapter for more information.
CRC (Cyclic Redundancy Check)
To verify data integrity and provide built-in error checking, a 16-bit CRC (Cyclic Redundancy
Check) is computed for the transmitted data and attached to the end of each RF packet. On the
receiving end, the receiving module computes the CRC on all incoming RF data. Received data that
has an invalid CRC is discarded [refer to the ‘Receive Mode’ section].
Receive Mode
If a module detects RF data while operating in Idle Mode, the module transitions to Receive Mode
to start receiving RF packets. Once a packet is received, the module checks the CRC (cyclic
redundancy check) to ensure that the data was transmitted without error. If the CRC data bits on
the incoming packet are invalid, the packet is discarded. If the CRC is valid, the packet proceeds to
the DO Buffer.
© 2012 Digi Internatonal, Inc.
14
XTend™ RF Module - Product Manual
Figure 2-07. Receive Mode Data Flow
* Refer to the ‘Address Recognition’ section for more information regarding
address recognition.
The module returns to Idle Mode
when valid RF data is no longer
detected or after an error is
detected in the received RF data. If
serial data is stored in the DI
buffer while the module is in
Receive Mode, the serial data will
be transmitted after the module is
finished receiving data and returns
to Idle Mode.
Shutdown Mode
Hardware Sleep
For applications where power consumption must be kept to a minimum during idle periods,
Shutdown Mode offers the lowest power mode available to the module.
When the SHDN pin (pin 7) is driven low, the module is forced into shutdown mode. Any
communication in progress (transmit or receive) will be halted and any buffered data will be lost.
For any other mode of operation, SHDN must be driven or pulled high. While in shutdown mode,
the module's VCC pin draws 5 µA (typical).
Immediately after the SHDN pin changes state from low to high, the module resets. After reset,
there is a delay that must be observed. Delay time is <100ms.
While SHDN pin is driven low, the following pins are set to high impedance by the module: DCD,
TX_PWR, RX LED, DO and CTS (See pin signal descriptions, p6). The SHDN line (also used for
RSSI indication) is driven low during shutdown.
The following input pins may continue to be driven by external circuitry when in shutdown mode:
PIN_PWR_DWN, RTS, DI and SHDN.
Note: Because the DO pin also goes high impedance, if the XTend RF Module is connected to a processor, the UART receive pin could be floating. A weak pull-up should be placed between the module
and the microcontroller so that data is not interpreted as being transmitted to the microprocessor.
Sleep Mode
Software Sleep
Sleep Modes enable the module to enter states of low-power consumption when not in use. Three
software Sleep Modes are supported:
• Pin Sleep (Host Controlled)
• Serial Port Sleep (Wake on Serial Port activity)
• Cyclic Sleep (Wake on RF activity)
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XTend™ RF Module - Product Manual
In order to enter Sleep Mode, one of the following conditions must be met (in addition to the
module having a non-zero SM parameter value):
1.
The module is idle (no data transmission or reception) for the amount of time defined by
the ST (Time before Sleep) parameter. [NOTE: ST is only active when SM = 4-5.]
2.
SLEEP (pin 8) is asserted (only for the ‘Pin Sleep’ option).
When in Sleep Mode, the module will not transmit or receive data until the module first transitions
to Idle Mode. All Sleep Modes are enabled and disabled using SM Command. Transitions into and
out of Sleep Modes are triggered by various mechanisms as shown in the table below.
Table 2-01.
Summary of Sleep Mode Configurations
Sleep Mode
(Setting)
Pin Sleep
(SM = 1)
Transition into
Sleep Mode
Assert (high) SLEEP pin - A micro
controller can shut down and wake
modules via the SLEEP pin.
Note: The module will complete a
transmission or reception before
activating Pin Sleep.
Transition out of Sleep
Mode (wake)
Related
Power
Commands Consumption
De-assert (low) SLEEP pin
(SM)
< 162 μA
(SM), ST
< 10 mA
Serial Port Sleep
(SM = 2)
Automatic transition to Sleep Mode
occurs after a user-defined period of
inactivity (no transmitting or receiving of When a serial byte is received on
data).
the DI pin
Period of inactivity is defined by the ST
(Time before Sleep) Command.
Cyclic Sleep
(SM = 4 - 8)
RF module transitions in and out of Sleep Mode in cycles (user-selectable
wake-up interval of time is set using the SM command). The cyclic sleep
interval of time must be shorter than the interval of time that is defined by the (SM), ST, HT,
LH (Wake-up Initializer TImer) command.
LH, PW
Note: The module can be forced into Idle Mode using the SLEEP pin if the PW
(Pin Wake-up) command is issued.
< 1.6 mA
when sleeping
(SM=4, 1 sec.,
@120K baud)
The SM (Sleep Mode) command is central to setting all Sleep Mode configurations. By default,
Sleep Modes are disabled (SM = 0) and the module remains in Idle/Receive Mode. When in this
state, the module remains constantly ready to respond to serial or RF activity.
Refer to the ‘Hardware Sleep’ section of the ‘Shutdown Mode’ section [previous page] to enable the
module's lowest power-consuming state (5 µA typical power-down current).
Pin Sleep (SM = 1)
• Pin/Host-controlled
• Typical power-down current: < 162 μA
This mode is voltage level activated. When the SLEEP pin is asserted, the module will finish any
transmitting or receiving activity; enter Idle Mode; then enter a state of sleep. When in Pin Sleep
Mode, the module will not respond to serial or RF activity.
After enabling Pin Sleep, the SLEEP pin controls whether the module is active or sleeping. When
SLEEP is de-asserted, the module is fully operational. When SLEEP is asserted, the module
transitions to Sleep Mode and remains in its lowest power-consuming state until the pin is deasserted. This pin is only active if the module is setup to operate in this mode; otherwise the pin is
ignored.
Once in Pin Sleep, CTS (GPO1) is de-asserted (high), indicating that data should not be sent to the
module. The PWR pin is also de-asserted (low) when the module is in Pin Sleep Mode.
Note: The module will complete a transmission or reception before activating Pin Sleep.
Serial Port Sleep (SM = 2)
• Wake on serial port activity
• Typical power-down current: < 10 mA
Serial Port Sleep is a Sleep Mode in which the module runs in a low power state until serial data is
detected on the DI pin.
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XTend™ RF Module - Product Manual
The period of time the module sleeps is determined by ST (Time before Sleep) Command. Once a
character is received through the DI pin, the module returns to Idle Mode and is fully operational.
Cyclic Sleep (SM = 4-8)
• Typical Power-down Current: < 1.6 mA (when asleep)
Cyclic Sleep Modes allow modules to periodically wake and check for RF data. The module wakes
according to the times designated by the Cyclic sleep settings. If the module detects a wake-up
initializer during the time it is awake, the module synchronizes with the transmitting module and
receives data after the wake-up initializer runs its duration. Otherwise, the module returns to
Sleep Mode and continues to cycle in and out of activity until a wake-up initializer is detected.
While the module is in Cyclic Sleep Mode, CTS (GPO1) is de-asserted (high) to indicate that data
should not be sent to the module. When the module awakens to listen for data, GPO1 is asserted
and any data received on the DI Pin is transmitted. The PWR pin is also de-asserted (low) when
the module is in Cyclic Sleep Mode.
The module remains in Sleep Mode for a user-defined period of time ranging from 0.5 seconds to
16 seconds (SM parameters 4 through 8). After this interval of time, the module returns to Idle
Mode and listens for a valid data packet. The listen time will depend on the [BR] (RF Data Rate)
parameter setting.The default [BR] setting of 1 will require at least a 35ms wake time, while the
[BR] setting of 0 will require a wake time of up to 225ms. If the module does not detect valid data
(on any frequency), the module returns to Sleep Mode. If valid data is detected, the module
transitions into Receive Mode and receives the incoming RF packets. The module then returns to
Sleep Mode after a period of inactivity determined by the ST "Time before Sleep" parameter.
The module can also be configured to wake from cyclic sleep when the SLEEP pin is de-asserted.
To configure a module to operate in this manner, PW (Pin Wake-up) Command must be issued.
Once the SLEEP pin is de-asserted, the module is forced into Idle Mode and can begin transmitting
or receiving data. It remains active until data is no longer detected for the period of time specified
by the ST Command, at which point it resumes its low-power cyclic state.
Cyclic Scanning. Each RF transmission consists of an RF Initializer and payload. The RF initializer
contains initialization information and all receiving modules must wake during the wake-up
initializer portion of data transmission in order to be synchronized with the transmitting module
and receive the data.
The cyclic interval time defined by the SM (Sleep Mode) command must be shorter than the interval
time defined by LH (Wake-up Initializer Timer) command.
Figure 2-08. Correct Configuration (LH > SM):
The length of the wake-up initializer exceeds the time interval of Cyclic Sleep. The receiver is
guaranteed to detect the wake-up initializer and receive the accompanying payload data.
Command Mode
To modify or read module parameters, the module must first enter into Command Mode (state in
which incoming characters are interpreted as commands). Two command types are supported:
• AT Commands
• Binary Commands
For modified parameter values to persist in the module registry, changes must be saved to nonvolatile memory using the WR (Write) command. Otherwise, parameters are restored to previously
saved values when the module is powered off and then on again.
© 2012 Digi Internatonal, Inc.
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XTend™ RF Module - Product Manual
AT Command Mode
To Enter AT Command Mode:
1.
Send the 3-character command sequence "+++" and observe guard times before and after
the command characters. [refer to ‘Default AT Command Mode Sequence’ below.] The ‘Terminal’ tab (or other serial communications software) of the X-CTU Software can be used to
enter the sequence.
[OR]
2.
Assert (low) the CONFIG pin and turn the power going to the module off and back on (or
pulse the SHDN pin).
[If the module is mounted to a Digi RS-232/485 Interface Board, the result can be achieved
by pressing the configuration switch down for 2 seconds.]
Default AT Command Mode Sequence (for transition to Command Mode):
• No characters sent for one second [refer to the BT (Guard Time Before) Command]
• Input three plus characters (“+++”) within one second
[refer to the CC (Command Sequence Character) Command.]
• No characters sent for one second [refer to the AT (Guard Time After) Command.]
All of the parameter values in the sequence can be modified to reflect user preferences.
To Send AT Commands:
Send AT commands and parameters using the syntax shown below.
Figure 2-09. Syntax for sending AT Commands
To read a parameter value stored in the module register, leave the parameter field blank.
The preceding example would change the module’s Destination Address to "0x1F". To store the
new value to non-volatile (long term) memory, the Write (ATWR) command must subsequently be
sent before powering off the module.
System Response. When a command is sent to the module, the module will parse and execute
the command. Upon successful execution of a command, the module returns an “OK” message. If
execution of a command results in an error, the module returns an “ERROR” message.
To Exit AT Command Mode:
1.
If no valid AT Commands are received within the time specified by CT (Command Mode
Timeout) Command, the module automatically returns to Idle Mode.
[OR]
2.
Send ATCN (Exit Command Mode) Command.
For an example of programming the RF module using AT Commands and descriptions of each configurable parameter, refer to the "RF Module Configuration" chapter [p20].
Binary Command Mode
Sending and receiving parameter values using binary commands is the fastest way to change
operating parameters of the module. Binary commands are used most often to sample signal
strength [refer to DB (Received Signal Strength) parameter] and/or error counts; or to change
module addresses and channels for polling systems when a quick response is necessary. Since the
sending and receiving of parameter values takes place through the same serial data path as 'live'
data (received RF payload), interference between the two types of data can be a concern.
Common questions about using binary commands:
• What are the implications of asserting CMD while live data is being sent or received?
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XTend™ RF Module - Product Manual
• After sending serial data, is there a minimum time delay before CMD can be asserted?
• Is a time delay required after CMD is de-asserted before payload data can be sent?
• How does one discern between live data and data received in response to a command?
The CMD pin (pin 10) must be asserted in order to send binary commands to the module. The
CMD pin can be asserted to recognize binary commands anytime during the transmission or
reception of data. The status of the CMD signal is only checked at the end of the stop bit as the
byte is shifted into the serial port. The application does not allow control over when data is
received, except by waiting for dead time between bursts of communication.
If the command is sent in the middle of a stream of payload data to be transmitted, the command
will essentially be executed in the order it is received. If the module is continuously receiving data,
the radio will wait for a break in the received data before executing the command. The CTS signal
will frame the response coming from the binary command request [refer to figure below].
A minimum time delay of 100 µs (after the stop bit of the command byte has been sent) must be
observed before the CMD pin can be de-asserted. The command executes after all parameters
associated with the command have been sent. If all parameters are not received within 0.5
seconds, the module returns to Idle Mode.
Note: When parameters are sent, they are two bytes long with the least significant byte sent first.
Binary commands that return one parameter byte must be written with two parameter bytes.
Commands can be queried for their current value by sending the command logically ORed (bitwise) with the value 0x80 (hexadecimal) with CMD asserted. When the binary value is sent (with
no parameters), the current value of the command parameter is sent back through the DO pin.
Figure 2-010.Binary Command Write then Read
Signal #4 is CMD
Signal #1 is the DI signal
Signal #2 is the DO signal from the radio
Signal #3 is CTS
In this graph, a value was written to a
register and then read out to verify it.
While not in the middle of other received
data, note that the CTS signal outlines the
data response out of the module.
IMPORTANT: In order for the module to recognize a binary command, the RT (GPI1 Configuration)
parameter must be set to one. If binary programming is not enabled (RT parameter value is not equal
to ‘1’), the module will not recognize that the CMD pin is asserted and therefore will not recognize the
data as binary commands.
Refer to [p20] for a binary programming example (DT command example returns two bytes).
© 2012 Digi Internatonal, Inc.
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3. RF Module Configuration
Programming Examples
Refer to the ‘Command Mode’ section [p17] for information regarding entrance into Command
Mode, sending AT commands and exiting Command Mode. Refer to the ‘X-CTU’ section [p72] of
the ‘Development Guide’ for more information regarding Digi’s configuration software.
AT Commands
To Send AT Commands (Using the ‘Terminal’ tab of the X-CTU Software)
Example: Utilize the 'Terminal' tab of the X-CTU Software to change the module's DT (Destination Address) parameter and save the new address to non-volatile memory. This example
requires the installation of Digi’s X-CTU Software and a serial connection to a PC.
Note: Do not send commands to the module
during flash programming (when parameters
are being written to the
module registry).
Wait for the "OK" system response that follows the ATWR
command before entering the next command
or use flow control.
Select the ‘Terminal’ tab of the X-CTU Software and enter the following command lines:
Method 1 (One line per command)
Send AT Command
+++
ATDT 
ATDT1A0D 
ATWR 
ATCN 
System Response
OK  (Enter into Command Mode)
{current value}  (Read Destination Address)
OK  (Modify Destination Address)
OK  (Write to non-volatile memory)
OK  (Exit Command Mode)
Method 2 (Multiple commands on one line)
Send AT Command
+++
ATDT 
ATDT1A0D,WR,CN 
System Response
OK  (Enter into Command Mode)
{current value}  (Read Destination Address)
OK  (Execute commands)
Note: When using X-CTU Software to program a module, PC com port settings must match the baud
(interface data rate), parity & stop bits parameter settings of the module. Use the 'Com Port Setup'
section of the “PC Settings” tab to configure PC com port settings to match those of the module.
Binary Commands
To Send Binary Commands:
Example: Use binary commands to change the RF module's destination address to 0x1A0D and
save the new address to non-volatile memory.
1.
2.
3.
4.
RT Command must be set to '1' in AT Command Mode to enable binary programming.
Assert CMD (Pin 10 is driven high). (Enter Binary Command Mode)
Send Bytes [parameter bytes must be 2 bytes long]:
00
(Send DT (Destination Address) Command)
0D
(Least significant byte of parameter bytes)
1A
(Most significant byte of parameter bytes)
08
(Send WR (Write) Command)
De-assert CMD (pin 10 is driven low). (Exit Binary Command Mode)
Note: CTS (pin 9) is high when a command is being executed. Hardware flow control must be disabled
as CTS will hold off parameter bytes.
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XTend™ RF Module - Product Manual
Command Reference Table
XTend Commands (The RF modules expect numerical values in hexadecimal. Hexadecimal values are
designated by a “0x” prefix. Decimal equivalents are designated by a “d” suffix.)
AT
Binary
Command Command
AT Command Name
Parameter Range
Command
Category
# Bytes
Factory
Returned Default
%V
0x3B (59d)
Board Voltage
0x2CCCA - 0x5BFFA [read-only]
Diagnostics
--
AM
0x40 (64d)
Auto-set MY
--
Networking & Security
--
--
AP v2.x20*
--
API Enable
0-2
Serial Interfacing
AT
0x05 (5d)
Guard Time After
2 - (ATST-3) [x 100 msec]
Command Mode Options 2
0x0A (10d)
BD
0x15 (21d)
Interface Data Rate
0 - 8 (standard rates)
0x39 - 0x1C9C38 (non-standard rates)
Serial Interfacing
BR
0x39 (57d)
RF Data Rate
0-1
RF Interfacing
BT
0x04 (4d)
Guard Time Before
0 - 0xFFFF [x 100 msec]
Command Mode Options 2
0x0A (10d)
CC
0x13 (19d)
Command Sequence Character
0x20 - 0x7F
Command Mode Options 1
0x2B ["+"] (43d)
CD
0x28 (40d)
GPO2 Configuration
0-4
Serial Interfacing
CF
--
Number Base
0-2
Command Mode Options 1
CN
0x09 (9d)
Exit Command Mode
--
Command Mode Options --
--
CS
0x1F (31d)
GPO1 Configuration
0-4
Serial Interfacing
CT
0x06 (6d)
Command Mode Timeout
2 - 0xFFFF [x 100 ms]
Command Mode Options 2
0xC8 (200d)
DB
0x36 (54d)
Received Signal Strength
0x6E - 0x28 [read-only]
Diagnostics
--
DT
0x00 (0d)
Destination Address
0 - 0xFFFF
Networking & Security
E0
0x0A (10d)
Echo Off
--
Command Mode Options --
--
E1
0x0B (11d)
Echo On
--
Command Mode Options --
--
ER
0x0F (15d)
Receive Error Count
0 - 0xFFFF
Diagnostics
FH
0x0D (13d)
Force Wake-up Initializer
--
Sleep (Low Power)
--
--
FL
0x07 (7d)
Software Flow Control
0-1
Serial Interfacing
FS
0x3E (62d)
Forced Sync Time
0 - 0xFFFF [x 10 msec]
RF Interfacing
FT
0x24 (36d)
Flow Control Threshold
0 - (DI buffer size - 0x11) [Bytes]
Serial Interfacing
DI buffer size
minus 0x11
GD
0x10 (16d)
Receive Good Count
0 - 0xFFFF
Diagnostics
HP
0x11 (17d)
Hopping Channel
0-9
Networking & Security
HT
0x03 (3d)
Time before Wake-up Initializer
0 - 0xFFFF [x 100 msec]
Sleep (Low Power)
0xFFFF
(65535d)
HV
--
Hardware Version
0 - 0xFFFF [read-only]
Diagnostics
--
ID
0x27 (39d)
Modem VID
0x11 - 0x7FFF (user-settable)
Networking & Security
0x8000 - 0xFFFF (factory-set, read-only)
0x3332
(13106d)
KY
0x3C (60d)
AES Encryption Key
0 - (64 hex digits all set to 'F')
Networking & Security
0 (disabled)
LH
0x0C (12d)
Wake-up Initializer Timer
0 - 0xFF [x 100 msec]
Sleep (Low Power)
MD v2.x20*
0x31 (49d)
RF Mode
0-6
Networking & Security
MK
0x12 (18d)
Address Mask
0 - 0xFFFF
Networking & Security
0xFFFF
(65535d)
MT
0x3D (61d)
Multi-Transmit
0 - 0xFF
Networking & Security
MY
0x2A (42d)
Source Address
0 - 0xFFFF
Networking & Security
0xFFFF
(65535d)
NB
0x23 (35d)
Parity
0-4
Serial Interfacing
PB v2.x20*
0x45 (69d)
Polling Begin Address
0 - 0xFFFF
Networking & Security
Networking & Security
Networking & Security
PD v2.x20*
0x47 (71d)
Minimum Polling Delay
0 - 0xFFFF
(Base: (x 1 ms), Remote: [x 10 ms])
PE v2.x20*
0x46 (70d)
Polling End Address
0 - 0xFFFF
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XTend™ RF Module - Product Manual
XTend Commands (The RF modules expect numerical values in hexadecimal. Hexadecimal values are
designated by a “0x” prefix. Decimal equivalents are designated by a “d” suffix.)
AT
Binary
Command Command
AT Command Name
Parameter Range
Command
Category
# Bytes
Factory
Returned Default
PK
0x29 (41d)
Maximum RF Packet Size
1 - 0x800 [Bytes]
RF Interfacing
varies
PL
0x3A (58d)
TX Power Level
0-4
RF Interfacing
4 (1 Watt)
PW
0x1D (29d)
Pin Wake-up
0-1
Sleep (Low Power)
RB
0x20 (32d)
Packetization Threshold
1 - Current value of PK
Serial Interfacing
0x800 (2048d)
RC
--
Ambient Power - Single Channel
0 - 0x31 [dBm, read-only]
Diagnostics
--
RE
0x0E (14d)
Restore Defaults
--
(Special)
--
--
RM
--
Ambient Power - All Channels
No parameter - 0x7D0
Diagnostics
--
RN
0x19 (25d)
Delay Slots
0 - 0xFF [slots]
Networking & Security
RO
0x21 (33d)
Packetization Timeout
0 - 0xFFFF [x UART character time]
Serial Interfacing
RP
0x22 (34d)
RSSI PWM Timer
0 - 0xFF [x 100 msec]
Diagnostics
0x20 (32d)
RR
0x18 (24d)
Retries
0 - 0xFF
Networking & Security
0x0A (10d)
RT
0x16 (22d)
GPI1 Configuration
0-2
Serial Interfacing
SB
0x37 (55d)
Stop Bits
0-1
Serial Interfacing
SH
0x25 (37d)
Serial Number High
0 - 0xFFFF [read-only]
Diagnostics
varies
SL
0x26 (38d)
Serial Number Low
0 - 0xFFFF [read-only]
Diagnostics
varies
SM
0x01 (1d)
Sleep Mode
0 - 8 (3 is reserved)
Sleep (Low Power)
ST
0x02 (2d)
Time before Sleep
(ATAT+3) - 0x7FFF [x 100 msec]
Sleep (Low Power)
0x64 (100d)
TP
0x38 (56d)
Board Temperature
0 - 0x7F [read-only]
Diagnostics
--
TR
0x1B (27d)
Delivery Failure Count
0 - 0xFFFF [read-only]
Diagnostics
TT
0x1A (26d)
Streaming Limit
0 - 0xFFFF [0 = disabled]
Networking & Security
TX
0x3F (63d)
Transmit Only
0-1
RF Interfacing
VL
--
Firmware Version - verbose
Returns string
Diagnostics
--
--
VR
0x14 (20d)
Firmware Version
0 - 0xFFFF [read-only]
Diagnostics
--
WA
--
Active Warning Numbers
Returns string
Diagnostics
--
--
WN
--
Warning Data
Returns string
Diagnostics
--
--
WR
0x08 (8d)
Write
--
(Special)
--
--
WS
--
Sticky Warning Numbers
Returns string
Diagnostics
--
--
* Firmware version in which command and parameter options were first supported
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XTend™ RF Module - Product Manual
Command Descriptions
Commands in this section are listed alphabetically. Command categories are designated between
the "< >" symbols that follow each command title. By default, XTend RF Modules expect numerical
values in hexadecimal since the default value of the CF (Number Base) Parameter is '1'.
Hexadecimal values are designated by the "0x" prefix and decimal values by the "d" suffix.
%V (Board Voltage) Command
 %V Command is used to read the
current voltage of the module circuit board.
AT Command: AT%V
Sample Output:
5.02 V (when ATCF = 0)
5051F (when ATCF = 1) *
5.02 (when ATCF = 2)
Parameter Range (read-only):
0x2CCCA - 0x5BFFA
(2.80 - 5.75 decimal)
* When CF = 1 (default), a hex integer is shown
that is equal to (voltage * 65536d).
Binary Command: 0x3B (59 decimal)
Number of bytes returned: 4
AM (Auto-set MY) Command
 AM Command is used
AT Command: ATAM
to automatically set the MY (Source Address)
Binary Command: 0x40 (64 decimal)
parameter from the factory-set serial number of
the module. The address is formed with bits 29,
28 and 13-0 of the serial number (in that order).
The resulting value is displayed as a result of this command.
AP (API Enable) Command
 The AP command is used to
enable the module to operate using the framebased API operation.
AT Command: ATAP
Parameter Range:0 - 2
Parameter
Configuration
API Disabled
(Transparent Operation)
API enabled
(w/out escaped
characters)
API enabled
(with escaped
characters)
Default Parameter Value:0
Number of Bytes Returned:1
Minimum Firmware Version Required: 2.x20
AT (Guard Time After) Command
 AT Command is used
to set/read the time-of-silence that follows the
command sequence character (CC Command) of
the AT Command Mode Sequence (BT + CC +
AT). By default, 1 second must elapse before and
after the command sequence character.
The times-of-silence surrounding the command
sequence character are used to prevent
inadvertent entrance into AT Command Mode.
AT Command: ATAT
Binary Command: 0x05 (5 decimal)
Parameter Range:2 - (ATST-3), up to 0x7FFC
[x 100 milliseconds]
Default Parameter Value: 0x0A (10 decimal)
Number of bytes returned: 2
Related Commands: BT (Guard Time Before),
CC (Command Sequence Character)
Refer to the ‘AT Command Mode’ section [p18] for
more information regarding the AT Command Mode Sequence.
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XTend™ RF Module - Product Manual
BD (Interface Data Rate) Command
 The BD command is used to
set and read the serial interface data rate (baud
rate) used between the RF module and host. This
parameter determines the rate at which serial
data is sent to the module from the host. Modified
interface data rates do not take effect until the CN
(Exit AT Command Mode) command is issued and
the system returns the 'OK' response.
AT Command: ATBD
Binary Command: 0x15 (21 decimal)
Parameter Ranges: 0 - 8 (standard rates)
0x39 - 0x1C9C38 (non-standard rates)
When parameters 0-8 are sent to the module, the
respective interface data rates are used (as
shown in the table on the right).
The RF data rate is not affected by the BD
parameter. If the interface data rate is set higher
than the RF data rate, a flow control configuration
may need to be implemented.
The range between standard and non-standard
baud rates (0x09 - 0x38) is invalid.
Parameter
Configuration (bps)
1200
2400
4800
9600
19200
38400
57600
115200
230400
Default Parameter Value: 3
Non-standard Interface Data Rates:
Non-standard baud rates supported as of
firmware v2.x20
Any value above 0x38 will be interpreted as an
actual baud rate. When a value above 0x38 is
Number of bytes returned: 4
sent, the closest interface data rate represented
by the number is stored in the BD register. For example, a rate of 19200 bps can be set by sending
the following command line "ATBD4B00". NOTE: When using Digi’s X-CTU Software, non-standard
interface data rates can only be set and read using the X-CTU ‘Terminal’ tab. Non-standard rates
are not accessible through the ‘Modem Configuration’ tab.
When the BD command is sent with a non-standard interface data rate, the UART will adjust to
accommodate the requested interface rate. In most cases, the clock resolution will cause the
stored BD parameter to vary from the parameter that was sent (refer to the table below). Reading
the BD command (send "ATBD" command without an associated parameter value) will return the
value actually stored in the module’s BD register.
Parameters Sent Versus Parameters Stored
BD Parameter Sent (HEX)
Interface Data Rate (bps)
BD Parameter Stored (HEX)
1200
19,200
115,200
12C
300
12B
1C200
115,200
1B207
BR (RF Data Rate) Command
 The BR command is used to set
and read the RF data rate (rate that RF data is
transmitted over-the-air) of the module.
AT Command: ATBR
Binary Command: 0x39 (57 decimal)
Parameter Range:0 - 1
Parameter
Baud (bps)
Configuration
9600
115200
Default Parameter Value:1
Number of bytes returned: 1
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BT (Guard Time Before) Command
 BT Command is
used to set the DI pin silence time that must
precede the command sequence character (CC
command) of the AT Command Mode sequence.
Refer to the ‘AT Command Mode’ section [p18] for
more information regarding the AT Command
Mode Sequence.
AT Command: ATBT
Binary Command: 0x04
Parameter Range: 0 - 0xFFFF
Default Parameter Value: 0x0A
Number of bytes returned: 2
CC (Command Sequence Character) Command
 The CC command
is used to set/read the ASCII character used
between guard times of the AT Command Mode
Sequence (BT + CC + AT). This sequence enters
the module into AT Command Mode so that data
entering the module (from the host) is recognized
as commands instead of payload.
Refer to the ‘AT Command Mode’ section [p18] for
more information regarding the AT Command
Mode Sequence.
AT Command: ATCC
Binary Command: 0x13 (19 decimal)
Parameter Range: 0x20 - 0x7F
Default Parameter Value: 0x2B (ASCII “+”)
Number of bytes returned: 1
Related Commands: AT (Guard Time After), BT
(Guard Time Before)
CD (GPO2 Configuration) Command
 CD Command is used to
select/read the behavior of the GPO2 line (pin 3).
AT Command: ATCD
Binary Command: 0x28 (40 decimal)
Parameter Range: 0 - 8 (standard rates)
Parameter
Configuration
RX LED
Default High
Default Low
(reserved)
RX LED
(valid address only)
Default Parameter Value: 2
Number of bytes returned: 1
CF (Number Base) Command
 CF command is used
to set/read the command formatting setting.
The following commands are always entered and
read in hex, no matter the CF setting:
VR (Firmware Version)
HV (Hardware Version)
KY (AES Encryption Key)
AT Command: ATCF
Parameter Range: 0 – 2
Parameter
Configuration
Commands utilize default
number base; decimal
commands may output units
All commands forced to
unsigned, unit-less hex
Commands utilize their
default number base; no
units are output
Default Parameter Value: 1
Number of bytes returned: 1
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CN (Exit AT Command Mode) Command
 The CN command is
used to explicitly exit the module from AT
Command Mode.
AT Command: ATCN
Binary Command: 0x09 (9 decimal)
CS (GPO1 Configuration) Command
 CS Command is used to
select the behavior of the GP01 pin (pin 9). This
output can provide RS-232 flow control, control
the TX enable signal (for RS-485 or RS-422
operations).
By default, GP01 provides RS-232 CTS (Clear-toSend) flow control.
AT Command: ATCS
Binary Command: 0x1F (31 decimal)
Parameter Range: 0 - 4
Parameter
Configuration
RS-232 CTS flow control
RS-485 TX enable low
High
RS-485 TX enable high
Low
Default Parameter Value: 0
Number of bytes returned: 1
Related Commands: RT (GPI1 Configuration),
TO (GP01 Timeout)
CT (Command Mode Timeout) Command
 The CT command is
used to set and read the amount of inactive time
that elapses before the module automatically
exits from AT Command Mode and returns to Idle
Mode.
Use the CN (Exit AT Command Mode) command
to exit AT Command Mode manually.
AT Command: ATCT
Binary Command: 0x06 (6 decimal)
Parameter Range:2 - 0xFFFF
[x 100 milliseconds]
Default Parameter Value: 0xC8 (200d)
Number of bytes returned: 2
Related Command: CN (Exit AT Command
Mode)
DB (Received Signal Strength) Command
 DB Command is used to read the
receive signal strength (in decibels relative to
milliWatts) of the last received packet. This
parameter is useful in determining range
characteristics of the RF modules under various
conditions.
AT Command: ATDB
Binary Command: 0x36 (54 decimal)
Parameter Range (read-only): 0x6E - 0x28
(-110 to -40 Decimal)
Number of bytes returned: 2
In default mode, this command shows the power level in signed decimal format with the units
(dBm). If CF = 1, the magnitude of the value is presented in unsigned hex. If CF = 2, the value is
presented in decimal, but without the units.
Sample Output:-88 dBm(when ATCF = 0)
58
(when ATCF = 1)
-88
(when ATCF = 2)
NOTE: If the DB register is read before the module has received an RF packet, the module will
return a value of 0x8000 (which means an RF packet has not yet been received).
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DT (Destination Address) Command
 DT Command is used to
set/read the networking address of an RF module.
The modules utilize three filtration layers: Vendor
ID Number (ATID), Channel (ATHP), and
Destination Address (ATDT). The DT command
assigns an address to a radio that enables it to
communicate with other radios in the network.
The simplest use of this command is that when
MY=0xFFFF and MK=0xFFFF on all radios in a
network, only radios with matching DT's will
communicate with each other.
AT Command: ATDT
Binary Command: 0x00
Parameter Range:0 - 0xFFFF
Default Parameter Value: 0
Number of bytes returned: 2
Related Commands: HP (Hopping Channel), ID
(Modem VID), MK (Address Mask), MY (Source
Address)
If MY is not 0xFFFF, then DT acts as a transmit address and MY acts as a receive address. For
example, MY can be set to unique values 1, 2, 3, etc. on unique radios in the network. Then set DT
on the transmitting radio to match the MY of the receiving radio you intend to communicate with.
Setting DT=0xFFFF will broadcast to all radios in the network. Refer to the 'Addressing' section
[p45] for more information.
E0 (Echo Off) Command
 E0 Command turns
off character echo in AT Command Mode.
By default, echo is off.
AT Command: ATE0
Binary Command: 0x0A (10 decimal)
E1 (Echo On) Command
 E1 Command enables
character echo in AT Command Mode. Each typed
character will be echoed back to the terminal
when ATE1 is active. E0 (Echo Off) is the default.
AT Command: ATE1
Binary Command: 0x0B (11 decimal)
ER (Receive Error Count) Command
 The ER command is used to set/
AT Command: ATER
read the number of receive-errors. The error
Binary Command: 0x0F (15 decimal)
count records the number of packets partially
Parameter Range: 0 - 0xFFFF
received then aborted on a reception error. This
value returns to 0 after a reset and is not nonDefault Parameter Value: 0
volatile (Value does not persist in the module's
Number of bytes returned: 2
memory after a power-up sequence). Once the
Related Commands: GD (Receive Good Count)
Receive Error Count reaches its maximum value
(up to 0xFFFF), it remains at its maximum count
value until the maximum count value is explicitly changed or the module is reset.
The ER parameter is not reset by pin, serial port or cyclic sleep modes.
FH (Force Wake-up Initializer) Command
 The FH command is used
AT Command: ATFH
to force a Wake-up Initializer to be sent on the
Binary Command: 0x0D (13 decimal)
next transmission. Use only with cyclic sleep
modes active on remote modules.
ATFH will not send a long header if ATHT = 0xFFFF. WR (Write) Command does not need to be
issued with FH Command.
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FL (Software Flow Control) Command
 The FL command is used to
configure software flow control. Hardware flow
control is implemented with the modual as the
GP01 pin (CTS pin of the RF module), which
regulates when serial data can be tranferred to
the module.
AT Command: ATFL
Binary Command: 0x07 (7 decimal)
Parameter Range:0 - 1
Default Parameter Value: 0
Number of bytes returned: 1
FL Command can also be used to allow software
flow control to be enabled. The XON character used is 0x11 (17 decimal). The XOFF character
used is 0x13 (19 decimal).
FS (Forced Synch Time) Command
 The FS command only applies
AT Command: ATFS
to streaming data. Normally, only the first packet
Binary Command: 0x3E (62 decimal)
of a continuous stream contains the full RF
Parameter Range:0 - 0xFFFF
initializer. The RF modules then remain
[x 10 milliseconds]
synchronized for subsequent packets of the
Default Parameter Value: 0
stream. This parameter can be used to
periodically force an RF initializer during such
Number of bytes returned: 2
streaming. Any break in UART character reception
long enough to drain the DI Buffer (UART receive buffer) and cause a pause in RF data
transmission will also cause an RF initializer to be inserted on the next transmission.
FT (Flow Control Threshold) Command
 The FT command is used to
set/read the flow control threshold. When FT
bytes have accumulated in the DI buffer (UART
Receive), CTS is de-asserted or the XOFF
software flow control character is transmitted.
AT Command: ATFT
Binary Command: 0x24 (36 decimal)
Parameter Range:
0 - (DI buffer size minus 0x11) [Bytes]
Default Parameter Value: DI Buffer size minus
0x11 (17 decimal)
Number of bytes returned: 2
GD (Receive Good Count) Command
 The GD command is used to set/
read the count of good received RF packets. Its
parameter value is reset to 0 after every reset
and is not non-volatile (The parameter value does
not persist in the RF module's memory after a
power-up sequence). Once the "Receive Good
Count" reaches its maximum value (up to
0xFFFF), it remains at its maximum count value
until the maximum count value is manually
changed or the module is reset.
AT Command: ATGD
Binary Command: 0x10 (16 decimal)
Parameter Range: 0 - 0xFFFF
Default Parameter Value: 0
Number of bytes returned: 2
Related Commands: ER (Receive Error Count)
The GD parameter is not reset by pin, serial port or cyclic sleep modes.
HP (Hopping Channel) Command
 The HP command is
used to set/read the RF module's hopping channel
number. A channel is one of three layers of
filtration available to the module.
In order for modules to communicate with each
other, the modules must have the same channel
number since each channel uses a different
© 2012 Digi Internatonal, Inc.
AT Command: ATHP
Binary Command: 0x11 (17 decimal)
Parameter Range: 0 - 9
Default Parameter Value: 0
Number of bytes returned: 1
Related Commands: ID (Modem VID), DT
(Destination Address), MK (Address Mask)
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XTend™ RF Module - Product Manual
hopping sequence. Different channels can be used to prevent modules in one network from
listening to transmissions of another.
HT (Time before Wake-up Initializer) Command
 The HT command is used
to set/read the time of inactivity (no serial or RF
data is sent or received) before a wake-up
initializer is sent by a TX (transmitting) RF
module. The HT parameter should be set shorter
than inactivity timeout [ST Command] time of
any RX (receiving) modules operating in Cyclic
Sleep (SM=4-8). The wake-up initializer sent by
the TX module instructs all RX modules to remain
awake to receive RF data.
AT Command: ATHT
Binary Command: 0x03 (3 decimal)
Parameter Range:0 - 0xFFFF
[x 100 milliseconds]
Default Parameter Value: 0xFFFF (wake-up
initializer will not be sent)
Number of bytes returned: 2
Related Commands: LH (Wake-up Initializer
Timer), SM (Sleep Mode), ST (Time before
Sleep)
From the RX module perspective: After HT time
elapses and the inactivity timeout [ST Command]
is met, the RX module goes into cyclic sleep. In cyclic sleep, the RX module wakes once per sleep
interval [SM Command] to check for a wake-up initializer. When a wake-up initializer is detected,
the module stays awake to receive data. The wake-up initializer must be longer than the cyclic
sleep interval to ensure that sleeping modules detect incoming data.
When HT time elapses, the TX module knows it needs to send a wake-up Initializer for all RX
modules to remain awake and receive the next transmission.
The main purpose of this command is to prevent the Long Header from being sent with every data
packet.
HV (Hardware Version) Command
 The HV command is used to read
the hardware version of the RF module.
AT Command: ATHV
Parameter Range:0 - 0xFFFF [Read-only]
Minimum Firmware Version Required: v1.x80
ID (Modem VID) Command
 The ID command is
used to set/read the VID (Vendor Identification
Number) of the RF module. RF modules must
have matching VIDs in order to communicate.
AT Command: ATID
Binary Command: 0x27 (39 decimal)
Parameter Range:
0x11 - 0x7FFF (user-settable)
0 - 0x10 & 0x8000 - 0xFFFF (factory-set)
Default Parameter Value: 0x3332 (13106d)
Number of bytes returned: 2
KY (AES Encryption Key) Command
 The KY command is
AT Command: ATKY
used to set the 256-bit AES (Advanced Encryption
Binary Command: 0x3C (60 decimal)
Standard) key for encrypting/decrypting data.
Parameter Range:
Once set, the key cannot be read out of the
0 - (64 hex digits all set to 'F')
module by any means. The entire payload of the
packet is encrypted using the key and the CRC is
Default Parameter Value: 0 (disabled)
computed across the ciphertext. When encryption
Number of bytes returned: 2
is enabled, each packet carries an additional 16
Number Base: Always Hexadecimal
bytes to convey the random CBC Initialization
Vector (IV) to the receiver(s). The KY value may
be “0” or any 256-bit value (= 64 hex digits = 32 bytes). Any other value, including entering ATKY
by itself with no parameters, causes an error.
A module with the wrong key (or no key) will receive encrypted data, but the data driven out the
serial port will be meaningless. Likewise, a module with a key will receive unencrypted data sent
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XTend™ RF Module - Product Manual
from a module without a key, but the output will be meaningless. Because CBC mode is utilized,
repetitive data appears differently in different transmissions due to the randomly-generated IV.
NOTE: For international (non-U.S.) variants of XTend modules, the encryption key is 128-bit AES.
The command operates the same except the key length is 16 bytes rather than 32 bytes. This
pertains to part numbers ending with -NA or -128 (the -NA and -128 suffix mean the same thing),
no matter what firmware version is loaded. This also pertains to the Australia version of firmware
22xx, no matter what part number XTend it is loaded onto.
LH (Wake-up Initializer Timer) Command
 The LH Command is used
to set/read the duration of time during which the
wake-up initializer is sent. When receiving
modules are in Cyclic Sleep Mode, they powerdown after a period of inactivity (as specified by
the ST parameter) and will periodically wake and
listen for transmitted data. In order for the
receiving modules to remain awake, they must
detect ~35ms of the wake-up initializer.
AT Command: ATLH
Binary Command: 0x0C (12 decimal)
Parameter Range:0 - 0xFF
[x 100 milliseconds]
Default Parameter Value: 1
Number of bytes returned: 1
Related Commands: HT (Time before Wake-up
Initializer), SM (Sleep Mode), ST (Time before
Sleep)
LH Command must be used whenever a receiving
module is operating in Cyclic Sleep Mode. The
Wake-up Initializer Time must be longer than the cyclic sleep time that [as determined by SM
(Sleep Mode) parameter]. If the wake-up initializer time were less than the Cyclic Sleep interval,
the connection would be at risk of missing the wake-up initializer transmission.
Refer to figures loated under the SM command description to view diagrams of correct and
incorrect configurations. The images emphasize that the LH value must be greater than the SM
value.
MD (RF Mode) Command
 The MD command is
used to select/read the settings that enable the
Polling and Repeater Modes on the module.
Polling Mode - A ‘Polling Base’ is responsible for
polling remotes. A ‘Polling Remote’ requires a poll
in order to transmit.
Repeater Mode - A ‘Repeater’ re-sends RF data
unless the transmission is addressed to it or if the
transmission has already been detected. A
‘Repeater End Node’ handles repeated messages,
but will not repeat the message over-the-air.
Refer to the Polling and Repeater Mode sections of
the ‘RF Communication Modes’ chapter for more
information.
AT Command: ATMD
Binary Command: 0x31 (49 decimal)
Parameter Range: 0 - 6
Parameter
Configuration
Transparent Operation
(Repeater Base)
[reserved - not used]
[reserved - not used]
Polling Base
Polling Remote
Repeater
Repeater End Node
Default Parameter Value: 0
Number of bytes returned: 1
Minimum Firmware Version Required: 2.x20
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MK (Address Mask) Command
 The MK command is
used to set/read the Address Mask of a module.
AT Command: ATMK
Binary Command: 0x12 (18 decimal)
All RF data packets contain the Destination
Parameter Range:0 - 0xFFFF
Address of the TX (transmitting) module. When a
Default Parameter Value: 0xFFFF (65535d)
packet is received, the TX module Destination
Address is logically "ANDed" (bitwise) with the
Number of bytes returned: 2
Address Mask of the RX (receiving) module. The
Related Commands: DT (Destination Address),
resulting value must match the Destination
HP (Hopping Channel), ID (Modem VID), MY
Address or Address Mask of the RX module for the
(Source Address)
packet to be received and sent out the RX
module's DO (Data Out) pin. If the "ANDed" value does not match the Destination Address or
Address Mask of the RX module, the packet is discarded.
Sniffer Mode (when MK = 0): ACK requests are ignored and every RX (receive) frame is sent to
the UART, without regard for repeated frames.
All “0” values are treated as irrelevant values and ignored.
Refer to the ‘Addressing’ section [p45] for more information.
MT (Multi-transmit) Command
 The MT command is
used to enabled multiple transmissions of RF data
packets. When Multi-transmit Mode is enabled
(MT > 0), packets do not request an ACK
(acknowledgement) from the receiving RF
module(s). MT takes precedence over RR, so if
both MT and RR are non-zero, then MT+1 packets
will be sent (with no ACK requests).
AT Command: ATMT
Binary Command: 0x3D (61 decimal)
Parameter Range: 0 - 0xFF
Default Parameter Value:0 (no forced
retransmissions)
Number of bytes returned: 1
Related Commands: Networking (DT, MK, MY,
When a receiving module receives a packet with
RN, TT), Serial Interfacing (BR, PK, RB, RO), RF
Interfacing (FS)
remaining forced retransmissions, it calculates
the length of the packet and inhibits transmission
for the amount of time required for all retransmissions. Thereafter, a random number of delay
slots are inserted between 0 and RN before transmission is allowed from the receiving module(s).
This prevents all listening modules from transmitting at once upon conclusion of a multiple
transmission event (when RN > 0).
NOTE: The actual number of forced transmissions is the parameter value plus one. For example, if
MT = 1, two transmissions of each packet will be sent.
Refer to the ‘Multi-transmit Mode’ section [p46] for more information.
MY (Source Address) Command
 The MY command is
used to set/read the Source Address of the RF
module.
Refer to the DT command and the 'Addressing'
section [p45] for more information.
AT Command: ATMY
Binary Command: 0x2A (42 decimal)
Parameter Range: 0 - 0xFFFF
Default Parameter Value: 0xFFFF (Disabled DT (Destination Address) parameter serves as
both source and destination address.)
Number of bytes returned: 2
Related Commands: DT (Destination Address),
HP (Hopping Channel), ID (Modem VID), MK
(Address Mask)
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NB (Parity) Command
 The NB command is used to
select/read the parity settings of the RF module
for UART communications.
AT Command: ATNB
Binary Command: 0x23 (35 decimal)
Parameter Range: 0 - 4
Parameter
Configuration
8-bit (no parity or
7-bit (any parity)
8-bit even
8-bit odd
8-bit mark
8-bit space
Default Parameter Value: 0
Number of bytes returned: 1
PB (Polling Begin Address) Command
 PB command is used to
set/read the module’s Polling Begin Address - the
first address polled Polling Mode is enabled.
AT Command: ATPB
Binary Command: 0x45 (69 decimal)
Parameter Range: 0 - 0xFFFF
Polling Operations: The ‘Polling Base’ (MD = 3)
Default Parameter Value: 0
cycles through a sequential range of addresses,
polling each ‘Polling Remote’ (MD = 4). The base
Number of bytes returned: 2
then waits for a response & proceeds to the next
Minimum Firmware Version Required: 2.x20
‘Polling Remote’. Each ‘Polling Remote’ responds
Related Commands: MD (RF Mode), PE (Polling
by sending the data from the Data In buffer
End Address), PD (Minimum Polling Delay)
following the RB & RO parameters. When there is
no eligible data to send, the ‘Polling Remote’ will not respond. The ‘Polling Base’ will move to the
next address in the polling sequence after a short delay.
PD (Minimum Polling Delay) Command
 The PD command is
used to set/read Polling Delay (Base, MD=3) or
Polling Timeout (Remote, MD=4).
Polling Delay (Base) is the time between polling
cycles. The Polling Base will start the polling cycle
after sending the first poll. After the polling cycle
has completed, the timer is restarted.
Polling Timeout (Remote) is the amount of time
the remote unit will hold data from the serial port
before discarding it. Data entered within the PD
time of the poll is transmitted and not discarded.
AT Command: ATPD
Binary Command: 0x47 (71 decimal)
Parameter Range: 0 - 0xFFFF
(Base: [x 1ms], Remote: [x 10ms])
Default Parameter Value: 0
Number of bytes returned: 2
Minimum Firmware Version Required: 2.x20
Related Commands: MD (RF Mode), PB (Polling
Begin Address), PE (Polling End Address)
PE (Polling End Address) Command
 PE command is used to
set/read the module’s Polling End Address - the
last address polled when Polling Mode is enabled.
AT Command: ATPE
Binary Command: 0x46 (70 decimal)
Parameter Range: 0 - 0xFFFF
Polling Operations: The ‘Polling Base’ (MD = 3)
Default Parameter Value: 0
cycles through a sequential range of addresses,
polling each ‘Polling Remote’ (MD = 4). The base
Number of bytes returned: 2
then waits for a response & proceeds to the next
Minimum Firmware Version Required: 2.x20
‘Polling Remote’. Each ‘Polling Remote’ responds
Related Commands: MD (RF Mode), PB (Polling
by sending data from the DI buffer following the
Begin Address), PD (Minimum Polling Delay)
RB & RO parameters. When there is no eligible
data to send, the ‘Polling Remote’ will not respond. The ‘Polling Base’ will move to the next address
in the polling sequence after a short delay.
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PK (Maximum RF Packet Size) Command
 The PK command is used to set/
read the maximum size of RF packets transmitted
from an RF module. The maximum packet size
can be used along with the RB and RO parameters
to implicitly set the channel dwell time.
If PK is set above 256 and BR is subsequently
changed to 0, PK will automatically be lowered to
256 and a warning will be raised (refer to the BR
(RF Data Rate) and WN (Warning Data)
commands for details).
AT Command: ATPK
Binary Command: 0x29 (41 decimal)
Parameter Range:1 - 0x800 [Bytes]
Default Parameter Value:0x100* or 0x800*
(256 or 2048 decimal)
Number of bytes returned: 2
Related Commands: BR (RF Data Rate) RB
(Packetization Threshold), RO (Packetization
Timeout), WN (Warning Data)
Changes to the PK parameter may have a
secondary effect on the RB (Packetization Threshold) parameter. RB must always be less than or
equal to PK. If PK is changed to a value that is less than the current value of RB, the RB value is
automatically lowered to be equal to PK.
* When BR = 0 (9600 baud), the maximum PK value is 0x100 (256d). When BR = 1 (115,200
baud), the maximum PK value is 0x800 (2048d).
PL (TX Power Level) Command
 The PL command is used to set/
read the power level at which the RF module
transmits data
AT Command: ATPL
Binary Command: 0x3A (58 decimal)
Parameter Range: 0 - 4
Parameter
Configuration
1 mW
10 mW
100 mW
500 mW
1000 mW (1 Watt)
Default Parameter Value: 4
Number of bytes returned: 1
PW (Pin Wake-up) Command
 Under normal operation, an
RF module in Cyclic Sleep Mode cycles from an
active state to a low-power state at regular
intervals until data is ready to be received. If the
PW parameter is set to 1, the SLEEP pin (pin 8)
can be used to awaken the module from Cyclic
Sleep. When the SLEEP Pin is de-asserted (low),
the module will be fully operational and will not go
into Cyclic Sleep.
Once the SLEEP pin is asserted, the module will
remain active for the period of time specified by
the ST (Time before Sleep) parameter and will
return to Cyclic Sleep Mode (if no data is ready to
be transmitted). PW Command is only valid if Cyclic
© 2012 Digi Internatonal, Inc.
AT Command: ATPW
Binary Command: 0x1D (29 decimal)
Parameter Range: 0 - 1
Parameter
Configuration
Disabled
Enabled
Default Parameter Value: 0
Number of bytes returned: 1
Related Commands: SM (Sleep Mode), ST
(Time before Sleep)
Sleep has been enabled.
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RB (Packetization Threshold) Command
 The RB command is used to
set/read the character threshold value.
AT Command: ATRB
RF transmission begins after data is received in
the DI Buffer and either of the following criteria is
met:
Parameter Range:0 - PK parameter value
(up to 0x800 Bytes)
• RB characters received by the UART
• RO character times of silence detected on the
UART receive lines (after receiving at least 1
Byte of data)
Binary Command: 0x20 (32 decimal)
Default Parameter Value: 0x800 Bytes
Number of bytes returned: 2
Related Commands: BR (RF Data Rate), PK (RF
Packet Size), RO (Packetization Timeout)
If PK (Max. RF Packet Size) is lowered below the
value of RB, RB is automatically lowered to match the PK value. If (RO = 0), RB bytes must be
received before beginning transmission.
Note: RB and RO criteria only apply to the first packet of a multi-packet transmission. If data
remains in the DI Buffer after the first packet, transmissions will continue in a streaming manner
until there is no data left in the DI Buffer (UART receive buffer).
RC (Ambient Power - Single Channel) Command
 The RC command is used to
examine and report the power level on a given
channel.
Sample output:-78 dBm [when CF = 0]
4e
[when CF = 1]
-78
[when CF = 2]
AT Command: ATRC
Parameter Range (read-only): 0 - 0x31 [dBm]
Number of bytes returned: 1
Related Commands: RM (Ambient Power - All
Channels)
RE (Restore Defaults) Command
 The RE command is used to
restore all configurable parameters to their
factory default settings.
AT Command: ATRE
Binary Command: 0x0E (14 decimal)
The RE Command does not cause default values
to be stored to non-volatile (persistent) memory. For the restored default settings to persist in the
module’s non-volatile memory and be saved in the event of RF module reset or power-down, the
WR (Write) command must be issued prior to power-down or reset.
RM (Ambient Power - All Channels) Command
 The RM command is used to
examine and report power levels on all channels.
If no parameter is given, the channels are
scanned one time. If a parameter is given, the
channels are repeatedly scanned for that number
of seconds. The maximum power level seen for
each channel is reported (i.e. peak hold).
AT Command: ATRM
Parameter Range: no parameter - 0x7D0)
Number of bytes returned: 2
Related Commands: RC (Ambient Power Single channel)
A graphical spectrum analyzer can be implemented by repeatedly sending the RM command (with
no arguments) and reading the resultant 50 power levels (this is easiest to do when CF = 1 or 2).
Sample output [when CF = 0]:
Sample output [when CF = 1]:
Sample output [when CF = 2]:
© 2012 Digi Internatonal, Inc.
Ch 0: -100 dBm
Ch 1: -103 dBm
...
Ch 49: -99 dBm
64
67
...
63
100
-103
…
-99
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XTend™ RF Module - Product Manual
RN (Delay Slots) Command
 The RN command is
used to set/read the time delay that the
transmitting RF module inserts before attempting
to resend a packet. If the transmitting module
fails to receive an acknowledgement after sending
a packet, it inserts a random number of delay
slots (ranging from 0 to (RN minus 1)) before
attempting to resend the packet. Each delay slot
is 5 msec (when BR=1) and 54 msec (when
BR=0).
AT Command: ATRN
Binary Command: 0x19 (25 decimal)
Parameter Range:0 - 0xFF [38 ms slots]
Default Parameter Value: 0
(no delay slots inserted)
Number of bytes returned: 1
Related Commands: RR (Retries), TT
(Streaming Limit)
If two modules attempt to transmit at the same time, the random time delay after packet failure
allows only one module to transmit the packet successfully; while the other module waits until the
channel available for RF transmission.
RN Command is only applicable if retries have been enabled [RR (Retries) Command] or if forced
delays will be inserted into a transmission [TT (Streaming Limit) Command].
RO (Packetization Timeout) Command
 The RO command is used to
set/read the Packetization Timeout setting. RF
transmission begins when data is in the DI buffer
and either of the following criteria are met:
• RO character times of silence on the UART
receive lines (after receiving at least 1 byte)
• RB characters have been received by the
UART
AT Command: ATRO
Binary Command: 0x21 (33 decimal)
Parameter Range:0 - 0xFFFF
[ x UART character times ]
Default Parameter Value: 3
Number of bytes returned: 2
Related Commands: RB (Packetization
RB and RO criteria only apply to the first packet of
Threshold)
a multi-packet transmission. If data remains in
the DI Buffer (UART receive) after the first packet, transmissions will continue in a streaming
manner until there is no data left in the DI Buffer.
When RO is the transmission-beginning criteria: The actual time between the reception of
the last character from the UART and the beginning of RF transmission will be at least 800 µsec
longer than the actual RO time to allow for transmission setup. Additionally, it is subject to 100200 µsec of additional uncertainty, which could be significant for small values of RO at high UART
bit rates.
The correct UART character time (10, 11, or 12 bits) is calculated based on the following criteria:
• 1 start bit
• 8 data bits
• 0 or 1 parity bit [as determined by the NB (Parity) Command)
• 1 or 2 stop bits [as determined by SB (Stop Bits) Command]
RP (RSSI PWM Timer) Command
 RP Command is used to enable a
PWM ("Pulse Width Modulation") output on the
Config/RSSI pin (pin 11 of the RF Module). The
pin is calibrated to show the difference between
received signal strength and the sensitivity level
of the RF module. PWM pulses vary from zero to
95 percent. Zero percent means the received RF
signal is at or below the published sensitivity level
of the module.
© 2012 Digi Internatonal, Inc.
AT Command: ATRP
Binary Command: 0x22 (34 decimal)
Parameter Range:0 - 0xFF
[x 100 milliseconds]
Default Parameter Value: 0x20 (32d)
Number of bytes returned: 1
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XTend™ RF Module - Product Manual
The following table shows dB levels above sensitivity and PWM values (The total time period of the
PWM output is 8.32 ms. PWM output consists of 40 steps and therefore the minimum step size is
0.208 ms.):
Table 3-01.
PWM Values
dBm above sensitivity
PWM percentage
(high period / total period)
10
20%
20
35%
30
50%
A non-zero value defines the time that PWM output is active with the RSSI value of the last
received RF packet. After the set time when no RF packets are received, PWM output is set low (0
percent PWM) until another RF packet is received. PWM output is also set low at power-up. A
parameter value of 0xFF permanently enables PWM output and always reflects the value of the last
received RF packet.
The Config/RSSI pin is shared between PWM output and Config input. When the module is
powered, the Config pin is an input. During the power-up sequence, if RP parameter is a non-zero
value, the Config pin is configured as an output and set low until the first RF packet is received.
With a non-zero RP parameter, the Config pin is an input for RP ms after power up.
RR (Retries) Command
 The RR command is
used to set/read the maximum number of retries
sent for a given RF packet. When RR Command is
enabled (RR>0), RF packet retries and ACKs
(acknowledgements) are enabled.
AT Command: ATRR
Binary Command: 0x18 (24 decimal)
Parameter Range:0 - 0xFF
Default Parameter Value: 0x0A (10 decimal)
Exceptions: If the MT command in enabled
Number of bytes returned: 1
(MT>0) or if a broadcast Destination Address is
used (DT = 0xFFFF); RF packet retries and ACKs are disabled.
After transmitting a packet, the transmitting RF module waits to receive an acknowledgement
from a receiving module. If the acknowledgement is not received in the period of time specified by
RN (Delay Slots) Command, the original packet is transmitted again. The RF packet is transmitted
repeatedly until an acknowledgement is received or until the packet is sent RR times.
RT (GPI1 Configuration) Command
 The RT command is used to
set/read the behavior of the GPI1 ping (pin 10) of
the RF Module. The pin can be configured to
enable binary programming or RTS flow control.
AT Command: ATRT
Binary Command: 0x16 (22 decimal)
Parameter Range:0 - 2
Default Parameter Value: 0
Number of bytes returned: 1
SB (Stop Bits) Command
 The SB Command is used to
set/read the number of stop bits in the data
packet.
AT Command: ATSB
Binary Command: 0x37 (55 decimal)
Parameter Range: 0 - 1
Parameter
Configuration
1 stop bit
2 stop bits
Default Parameter Value: 0
Number of bytes returned: 1
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XTend™ RF Module - Product Manual
SH (Serial Number High) Command
 SH Command is used to set/read
the serial number high word of the RF module.
AT Command: ATSH
Binary Command: 0x25 (37 decimal)
Parameter Range (read-only): 0 - 0xFFFF
Default Parameter Value: varies
Number of bytes returned: 2
Related Commands: SL (Serial Number Low)
SL (Serial Number Low) Command
 SL Command is used to set/read
the serial number low word of the RF module.
AT Command: ATSL
Binary Command: 0x26 (38 decimal)
Parameter Range (read-only): 0 - 0xFFFF
Default Parameter Value: varies
Number of bytes returned: 2
Related Commands: SH (Serial Number High)
SM (Sleep Mode) Command
 The SM Command is
used to set/read the RF module's Sleep Mode
settings that configure the module to run in states
that require minimal power consumption.
For more information regarding Sleep Modes,
refer to the Sleep Mode sections [p15]
AT Command: ATSM
Binary Command: 0x01
Parameter Range: 0 - 8 (3 is reserved)
Parameter
Configuration
Disabled
Pin Sleep
Serial Port Sleep
[reserved]
Cyclic 1.0 second sleep
(RF module wakes every
1.0 seconds)
Cyclic 2.0 second sleep
Cyclic 4.0 second sleep
Cyclic 8.0 second sleep
Cyclic 16.0 second sleep
Default Parameter Value: 0
Number of bytes returned: 1
Related Commands:
Pin Sleep - PC (Power-up Mode), PW (Pin
Wake-up)
Serial Port Sleep - ST (Time before Sleep)
Cyclic Sleep - ST (Time before Sleep), LH
(Wake-up Initializer Timer), HT (Time Before
Wake-up Initializer), PW (Pin Wake-up)
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XTend™ RF Module - Product Manual
ST (Time before Sleep) Command
 The ST Command is
used to set/read the period of time (in
milliseconds) in which the RF module remains
inactive before entering Sleep Mode.
For example, if the ST Parameter is set to 0x64
(100 decimal), the module will enter into Sleep
mode after 10 seconds of inactivity (no
transmitting or receiving).
This command can only be used if Cyclic Sleep or
Serial Port Sleep Mode settings have been
selected using SM (Sleep Mode) Command.
AT Command: ATST
Binary Command: 0x02 (2 decimal)
Parameter Range:(ATAT+3) - 0x7FFF
[x 100 milliseconds]
Default Parameter Value: 0x64 (100 decimal)
Number of bytes returned: 2
Related Commands: SM (Sleep Mode), LH
(Wake-up Initializer Timer), HT (Time before
Wake-up Initializer)
TP (Board Temperature) Command
 TP Command is used to read the
current temperature of the board.
AT Command: ATTP
Sample Output:26 C[when ATCF = 0]
1A
[when ATCF = 1]
26
[when ATCF = 2].
Parameter Range (read-only): 0- 0x7F
Binary Command: 0x38 (56 decimal)
Number of bytes returned: 1
Related Command: WN (Warning Data)
TR (Transmit Error Count) Command
 The TR command is used to report
the number of retransmit failures. This number is
incremented each time a packet is not
acknowledged within the number of retransmits
specified by the RR (Retries) parameter. The
number of packets therefore are counted that
were not successfully received and subsequently
discarded.
AT Command: ATTR
Binary Command: 0x1B (27 decimal)
Parameter Range: 0 - 0xFFFF
Default Parameter Value: 0
Number of bytes returned: 2
Related Commands: RR (Retries)
The TR parameter is not non-volatile and is reset to zero when the RF module is reset.
TT (Streaming Limit) Command
 The TT command is
used to set/read the limit on the number of bytes
that can be sent out before a random delay is
issued.
AT Command: ATTT
Binary Command: 0x1A (26 decimal)
Parameter Range:0 - 0xFFFF
Default Parameter Value: 0 (disabled)
If an RF module is sending a continuous stream of
RF data, a delay is inserted which stops its
Number of bytes returned: 2
transmission and allows other modules time to
Related Commands: RN (Delay Slots)
transmit (once it sends TT bytes of data).
Inserted random delay lasts between 1 & 'RN + 1' delay slots, where each delay slot lasts 38 ms.
The TT command can be used to simulate full-duplex behavior.
© 2012 Digi Internatonal, Inc.
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XTend™ RF Module - Product Manual
TX (Transmit Only) Command
 The TX command is used to set/
read the transmit/receive behaviors of the RF
module. Setting a module to TX-only (TX = 1)
may reduce latency because the transmitting
module will never be confined to receiving data
from other modules.
AT Command: ATTX
Binary Command: 0x3F (63 decimal)
Parameter Range: 0 - 1
Parameter
Configuration
TX & RX
TX-only
Default Parameter Value: 0
Number of bytes returned: 1
VL (Firmware Version - Verbose)
 The VL command is used to read
the verbose firmware version of the RF module.
AT Command: ATVL
Parameter Range: returns string
Default Parameter Value: 0
Number of bytes returned: 2
VR (Firmware Version - Short) Command
© 2012 Digi Internatonal, Inc.
 The VR command is used to read
the firmware version of the RF module.
AT Command: ATVR
Note: Firmware versions contain four significant
digits - “A.B.C.D”. If B=2, the module is
programmed for operation in Australia only.
Parameter Range (read-only): 0 - 0xFFFF
Binary Command: 0x14 (20 decimal)
Number of bytes returned: 2
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XTend™ RF Module - Product Manual
WA (Active Warning Numbers) Command
 The WA command reports the
warning numbers of all active warnings - one
warning number per line. No further information
is shown and warning counts are not reset.
AT Command: ATWA
Parameter Range:Returns string - one
warning number per line.
Sample Output (indicates warnings 1 and 3 are currently active):1
OK
WN (Warning Data) Command
 WN command is used to report the
following data for all active and sticky warnings:
• Warning number & description
AT Command: ATWN
Parameter Range: returns string
• Number of occurrences since the last WN or WS command
• Whether the warning is currently active
Warnings, which are not currently active and have not been active since the last issuance of the
WN or WS commands, are not displayed. The WN command also resets all non-zero warning
counts; except for warnings that are presently active, which are set to 1.
Sample output:Warning 4: Over-temperature
5 occurrences; presently inactive.
Warning #
Description
Under-voltage. This is caused if the supply voltage falls below the minimum threshold for the lowest power level (2.8 V). If/when the voltage
rises above the threshold, the warning is deactivated. The module will not transmit below this voltage threshold.
Over-voltage. This is caused if the supply voltage exceeds 5.75 V. Transmission is not allowed while this warning is active.
Under-temperature. This is caused if the temperature sensed by the module is less than -40 C. The module does not artificially limit operation
while this warning is active, but module functionality is not guaranteed.
Over-temperature. This is caused if the temperature sensed by the module is greater than 105 C. The module does not allow transmission nor
reception while this warning is active. The warning is deactivated when the temperature falls to 100 C.
Power reduced. This is caused if the transmit power has to be reduced from the level programmed by PL Command due to insufficient supply
voltage. The 1 W power level requires 4.75 V or higher; 500 mW requires 3.0 V or higher; 100 mW, 10 mW and 1 mW require 2.8 V or higher.
Default calibration data in flash. This is caused if the module-specific power calibration data is either not present or is invalid, or if none of the
parameters have been modified from their default values. Power levels may be incorrect.
Default configuration parameters in flash. This is caused if user-modifiable parameters (i.e. those stored by a 'WR' command) in flash are all the
compiled-in default values. This is caused if the user configuration is found to be not present or invalid at power-up and there is no custom
configuration, or if no user-modifiable parameters have been modified from the compiled-in defaults. Modification of one or more parameters
without the subsequent WR to commit the changes to flash will not deactivate this warning, since it reflects the status of the parameters in flash.
Note that this warning does not reflect usage of the custom configuration defaults, only usage of the compiled-in defaults.
Default factory configuration parameters in flash. This is caused if the factory parameters in flash are all the default values. This is caused if the
factory configuration is found to be not present or invalid at power-up, or if no factory parameters have been modified.
WR (Write) Command
<(Special)> The WR command is used to write
configurable parameters to non-volatile memory
(Values remain in the module's memory until
overwritten by another use of WR Command).
AT Command: ATWR
Binary Command: 0x08
If changes are made without writing them to non-volatile memory, the module will revert back to
previously saved parameters the next time the module is powered-on.
If the non-volatile user configuration is not correct, WR will re-attempt (up to 3x). If all three
attempts fail, the command will return an ERROR alert.
WS (Sticky Warning Numbers) Command
 The WS command reports warning
AT Command: ATWS
numbers of all warnings active since the last use
Parameter Range (read-only): 1 - 8
of the WS or WN command (including any
Number of bytes returned: 1
warnings which are currently active). This
command also resets all non-zero warning counts,
except for warnings that are presently active, which are set to 1.
© 2012 Digi Internatonal, Inc.
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XTend™ RF Module - Product Manual
API Operation
By default, XTend RF Modules act as a serial line replacement (Transparent Operation) - all UART
data received through the DI pin is queued up for RF transmission. When the module receives an
RF packet, the data is sent out the DO pin with no additional information.
Inherent to Transparent Operation are the following behaviors:
• If module parameter registers are to be set or queried, a special operation is required for
transitioning the module into Command Mode [refer to p17].
• In point-to-multipoint systems, the application must send extra information so that the
receiving module(s) can distinguish between data coming from different remotes.
As an alternative to the default Transparent Operation, API (Application Programming Interface)
Operations are available. API operation requires that communication with the module be done
through a structured interface (data is communicated in frames in a defined order). The API
specifies how commands, command responses and module status messages are sent and received
from the module using a UART data frame.
API Frame Specifications
Two API modes are supported and both can be enabled using the AP (API Enable) command. Use
the following AP parameter values to configure the module to operate in a particular mode:
• AP = 0 (default): Transparent Operation (UART Serial line replacement)
API modes are disabled.
• AP = 1: API Operation
• AP = 2: API Operation (with escaped characters)
Any data received prior to the start delimiter is silently discarded. If the frame is not received
correctly or if the checksum fails, the data is silently discarded.
API Operation (AP parameter = 1)
When this API mode is enabled (AP = 1), the UART data frame structure is defined as follows:
Figure 3-01. UART Data Frame Structure:
Start Delimiter
(Byte 1)
0x7E
Length
(Bytes 2-3)
MSB
LSB
Frame Data
(Bytes 4-n)
Checksum
(Byte n + 1)
API-specific Structure
1 Byte
MSB = Most Significant Byte, LSB = Least Significant Byte
API Operation - with Escape Characters (AP parameter = 2)
When this API mode is enabled (AP = 2), the UART data frame structure is defined as follows:
Figure 3-02. UART Data Frame Structure - with escape control characters:
Start Delimiter
(Byte 1)
0x7E
Length
(Bytes 2-3)
MSB
LSB
Frame Data
(Bytes 4-n)
Checksum
(Byte n + 1)
API-specific Structure
1 Byte
Characters Escaped If Needed
MSB = Most Significant Byte, LSB = Least Significant Byte
Escape characters. When sending or receiving a UART data frame, specific data values must be
escaped (flagged) so they do not interfere with the UART or UART data frame operation. To escape
an interfering data byte, insert 0x7D and follow it with the byte to be escaped XOR’d with 0x20.
© 2012 Digi Internatonal, Inc.
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XTend™ RF Module - Product Manual
Data bytes that need to be escaped:
• 0x7E – Frame Delimiter
• 0x7D – Escape
• 0x11 – XON
• 0x13 – XOFF
Example - Raw UART Data Frame (before escaping interfering bytes):
0x7E 0x00 0x02 0x23 0x11 0xCB
0x11 needs to be escaped which results in the following frame:
0x7E 0x00 0x02 0x23 0x7D 0x31 0xCB
Note: In the above example, the length of the raw data (excluding the checksum) is 0x0002 and
the checksum of the non-escaped data (excluding frame delimiter and length) is calculated as:
0xFF - (0x23 + 0x11) = (0xFF - 0x34) = 0xCB.
Checksum
To test data integrity, a checksum is calculated and verified on non-escaped data.
To calculate: Not including frame delimiters and length, add all bytes keeping only the lowest 8
bits of the result and subtract from 0xFF.
To verify: Add all bytes (include checksum, but not the delimiter and length). If the checksum is
correct, the sum will equal 0xFF.
API Types
Frame data of the UART data frame forms an API-specific structure as follows:
Figure 3-03. UART Data Frame & API-specific Structure:
Start Delimiter
(Byte 1)
0x7E
Length
(Bytes 2-3)
MSB
LSB
Frame Data
(Bytes 4- n)
Checksum
(Byte n + 1)
API-specific Structure
1 Byte
API Identifier
Identifier-specific Data
cmdID
cmdData
The cmdID frame (API-identifier) indicates which API messages will be contained in the cmdData
frame (Identifier-specific data). Refer to the sections that follow for more information regarding
the supported API types. Note that multi-byte values are sent big endian.
RF Module Status
API Identifier: 0x8A
RF module status messages are sent from the module in response to specific conditions.
Figure 3-04. RF Module Status Frames
Start Delimiter
0x7E
Length
MSB
LSB
Frame Data
Checksum
API-specific Structure
1 Byte
API Identifier
Identifier-specific Data
0x8A
cmdData
Status (Byte 5)
0 = Hardware reset
1 = Watchdog timer reset
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XTend™ RF Module - Product Manual
TX (Transmit) Request: 16-bit address
API Identifier Value: 0x01
A TX Request message will cause the module to send RF Data as an RF Packet.
Figure 3-5.
TX Packet (16-bit address) Frames
Start Delimiter
Length
0x7E
MSB
LSB
Frame Data
Checksum
API-specific Structure
1 Byte
API Identifier
Identifier-specific Data
0x01
cmdData
Frame ID (Byte 5)
Destination Address (Bytes 6-7)
Identifies the UART data frame for the host to
correlate with a subsequent ACK (acknowledgement).
Setting Frame ID to ‘0' will disable response frame.
Figure 3-6.
Byte 1
0x7E
Start Delimiter
Options (Byte 8)
MSB first, LSB last.
Broadcast = 0xFFFF
0 = Standard
1 = Disable ACK
RF Data (Byte(s) 9-n)
Up to 2048 Bytes per packet
Example: TX Packet API Frames
Bytes 2-3
0x00
Byte 4
Byte 5
Bytes 6-7
Byte 8
Bytes 9-11
Byte 12
0x01
R (0x52)
0xFFFF
0x00
1 (0x31) 2 (0x32) 3 (0x33)
0x18
API Identifier
Frame ID**
Destination Address
Option
RF Data
Checksum
0x08
Length*
* Length [Bytes] = API Identifier + Frame ID + Option + RF Data
** “R” value was arbitrarily selected
TX (Transmit) Status
API Identifier Value: 0x89
When a TX Request is completed, the module sends a TX Status message. This message will
indicate if the packet was transmitted successfully or if there was a failure.
Figure 3-7.
TX Status Frames
Start Delimiter
Length
0x7E
MSB
LSB
Frame Data
Checksum
API-specific Structure
1 Byte
API Identifier
Identifier-specific Data
0x89
cmdData
Frame ID (Byte 5)
Status (Byte 6)
Identifies UART data frame being reported.
Note: If Frame ID = 0 in the TX Request, no
AT Command Response will be given.
0 = Success
1 = No ACK (Acknowledgement) received
NOTE: “STATUS = 1” occurs when all retries are expired and no ACK is received.
“STATUS = 3” occurs when a packet is purged due to a ‘Polled Remote’ not receiving a poll.
RX (Receive) Packet: 16-bit address
API Identifier Value: 0x81
When the module receives an RF packet, it is sent out the UART using this message type.
Figure 3-8.
Start Delimiter
0x7E
Source Address (Bytes 5-6)
MSB (most significant byte) first,
LSB (least significant) last
© 2012 Digi Internatonal, Inc.
RX Packet (16-bit address) Frames
Length
MSB
LSB
Frame Data
Checksum
API-specific Structure
1 Byte
API Identifier
Identifier-specific Data
0x81
cmdData
RSSI (Byte 7)
Received Signal Strength Indicator Hexadecimal equivalent of (-dBm) value.
(For example: If RX signal strength = -40
dBm, “0x28” (40 decimal) is returned)
Options (Byte 8)
bit 0 = ACK
bit 1 = Indicate broadcast
bits 2-7 [reserved]
RF Data (Byte(s) 9-n)
Up to 2048 Bytes per
packet
43
4. RF Communication Modes
The network configurations covered in this chapter are described in terms of the following:
• Network Topology (Point-to-Point, Point-to-Multipoint or Peer-to-Peer)
• RF Communication Type (Basic or Acknowledged)
• RF Mode (Streaming, Multi-Transmit, Repeater, Acknowledged or Polling)
Note: Please see the DigiMesh chapter for additional information on networking features.
The following table provides a summary of the network configurations supported.
Table 4-01.
Summary of network topologies supported by the XTend RF Module
Point-to-Point
Definition
An RF data link between two modules.
Sample Network Profile *
(Broadcast Communications)
Use default values for all modules.
Sample Network Profile *
(Acknowledged Communications)
All modules:
ATAM [auto-set MY (Source Address) parameter] **
ATDT FFFF [set Destination Address to 0xFFFF]
Basic RF Modes
Streaming, Multi-Transmit, Repeater
Acknowledged RF Mode
Acknowledged Mode
Definition
RF data links between one base and multiple remotes.
Point-to-Multipoint
Sample Network Profile *
(Basic Communications)
Base:
ATMY 0 [set Source Address to 0x00]
ATDT FFFF [set Destination Address to 0xFFFF]
Remotes:
ATAM [auto-set MY (Source Address) parameter] **
ATDT 0 [set Destination Address to 0x00]
Base:
ATMY 0 [set Source Address to 0x00]
ATDT FFFF [set Destination Address to 0xFFFF]
ATRR 3 [set number of Retries to 3]
Remotes:
ATAM [auto-set MY (Source Address) parameter] **
ATDT 0 [set Destination Address to 0x00]
ATRR 3 [set number of Retries to 3]
Sample Network Profile *
(Acknowledged Communications)
Basic RF Modes
Streaming, Multi-Transmit, Repeater, Polling
Acknowledged RF Modes
Acknowledged, Polling
Definition
RF modules remain synchronized without use of master/server
dependencies. Each module shares the roles of master and slave.
Digi's peer-to-peer architecture features fast synch times (35ms to
synchronize modules) and fast cold start times (50ms before
transmission).
Sample Network Profile *
(Basic Communications)
Use default values for all modules.
Sample Network Profile *
(Acknowledged Communications)
ATAM [auto-set MY (Source Address) parameter] **
All modules: ATDT FFFF [set Destination Address to 0xFFFF]
ATRR 3 [set number of Retries to 3]
Basic RF Mode
Streaming
Acknowledged RF Mode
Acknowledged
Peer-to-Peer
* Assume default values for parameters not listed. Profiles do not reflect addressing implementations.
** AM (Auto-set MY) Command must be issued through a terminal program such as the one incorporated in the
X-CTU 'Terminal' tab.
© 2012 Digi International Inc.
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XTend™ RF Module - Product Manual
Addressing
Each RF packet contains addressing information that is used to filter incoming RF data. Receiving
modules inspect the Hopping Channel (HP parameter), Vendor Identification Number (ID
parameter) and Destination Address (DT parameter) contained in each RF packet. Data that does
not pass through all three network security layers is discarded.
Figure 4-01. Addressing layers contained in the RF packet header
Address Recognition
Transmissions can be addressed to a specific module or group of modules using the DT
(Destination Address) and MK (Address Mask) commands. A receiving module will only accept a
packet if it determines the packet is addressed to it, either as a global or local packet. The
receiving module makes this determination by inspecting the destination address of the packet
and comparing it to its own address and address mask [refer to the figure below].
Figure 4-02. Address Recognition (@ the Receiving RF Module)
TX_DT = Destination Address of transmitting module
RX_DT = Destination Address of receiving module
RX_MK = Address Mask of receiving module
RX_MY = Source Address of receiving module
The transmitting module determines whether the packet is intended for a specific node (local
address) or multiple nodes (global address) by comparing the packet's destination address (DT)
and its own address mask (MK) [refer to the figure below]. It is assumed that the address masks
on the transmitting module and receiving module have been programmed to the same value for
proper operation in each RF Communication Mode.
Figure 4-03. Address Recognition (@ the Transmitting RF Module)
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XTend™ RF Module - Product Manual
Basic Communications
Basic Communications are accomplished through two sub-types:
• Broadcast - By default, XTend RF Modules communicate through Broadcast communications
and within a peer-to-peer network topology. When any module transmits, all other modules
within range will receive the data and passit directly to their host device.
• Addressed - If addressing parameters match are in order, received RF data is forwarded to the
DO (Data Out) buffer; otherwise, the RF data is discarded.
When using Basic Communications, any functions such as acknowledgements are handled at the
application layer by the integrator. The Broadcast Modes provide transparent communications,
meaning that the RF link simply replaces a wired link.
Streaming Mode (Default)
Characteristics:Highest data throughput
Lowest latency and jitter
Reduced immunity to interference
Transmissions never acknowledged (ACK) by receiving module(s)
Required Parameter Values (TX module): RR (Retries) = 0
Related Commands: Networking (DT, MK, MY), Serial Interfacing (PK, RB, RO, TT)
Recommended Use: Mode is most appropriate for data systems more sensitive to latency and/or
jitter than to occasional packet loss. For example: streaming audio or video.
Connection Sequence
Figure 4-04. Streaming Mode State Diagram (TX Module)
• Events & processes in this mode are common to all of
the other RF Modes.
• When streaming data, RB and RO parameters are only
observed on the first packet.
After transmission begins, the transmission event will
continue uninterrupted until the DI buffer is empty or the
streaming limit (TT parameter) is reached. As with the first
packet, the payload of each subsequent packet includes up
to the maximum packet size (PK parameter).
The TT parameter (streaming limit) is specified by the TX
(transmitting) module as the maximum number of bytes the
TX module can send in one transmission event. After the TT
parameter threshold is reached, the TX module will force a
random delay of 1 to RN delay slots (exactly 1 delay slot if
RN = 0).
Subsequent packets are sent without an RF initializer since
RX (receiving) modules remain synchronized with the TX
module for the duration of the transmission (from preceding
packet information). However, due to interference, some RX
modules may lose data (and synchronization to the TX
module), particularly during long transmission events.
Once the TX module has sent all pending data or has
reached the TT limit, the transmission event ends. The TX
module will not transmit again for exactly RN delay slots if
the local (i.e. TX module's) RN parameter is set to a nonzero value. The RX module(s) will not transmit for a random
number of delay slots between 0 and (RN-1) if the local (i.e.
receiving module's) RN parameter is set to a non-zero
value. These delays are intended to lessen congestion
following long bursts of packets from a single TX module,
during which several RX modules may have become ready to transmit.
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XTend™ RF Module - Product Manual
Multi-transmit Mode
Attributes:Reliable Delivery through forced transmission of every RF packet
Every RF packet is sent exactly (MT + 1) times with no delays between packets
Diminished throughput and increased latency
Required Parameter Values (TX module): MT (Multi-Transmit) >= 1
Other Related Commands: Networking (DT, MK, MY, RN, TT), Serial Interfacing (BR, PK, RB,
RO), RF Interfacing (FS)
Recommended Use: Use for applications that require Reliable Delivery without using retries and
acknowledgements.
Connection Sequence
Figure 4-05. Multi-Transmit Mode State Diagram
(TX Module)
In Multi-Transmit Mode, each packet is
retransmitted MT times, for a total of (MT+1)
transmissions. There is no delay between
retransmissions, and the TX (transmitting)
module will never receive RF data between
retransmissions. Each retransmission includes
an RF initializer. A transmission event may
include follow-on packets, each of which will be
retransmitted MT times. The Forced Sync (FS)
parameter is ignored in Multi-Transmit Mode.
The RB and RO parameters are not applied to
follow-on packets, meaning that once
transmission has begun, it will continue
uninterrupted until the DI buffer is empty or
the streaming limit (TT parameter) has been
reached. As with the first packet, the payload
of each follow-on packet includes up to the
maximum packet size (PK parameter) bytes,
and the TX module checks for more pending
data near the end of each packet. Follow-on
packets are not sent until all retransmissions of
the previous packet are finished.
The streaming limit (TT) is specified at the TX
module as the maximum number of bytes that
the TX module can send in one transmission
event, which may consist of many packets. If
the TT parameter is reached, the TX module
will force a random delay of 1 to RN delay slots
(exactly 1 delay slot if RN is zero). In MultiTransmit Mode, each packet is counted only
once when tracking the streaming limit (TT),
no matter how many times it is retransmitted.
When an RX (receiving) module receives a
Multi-Transmit packet, it calculates the amount
of time remaining in the Multi-Transmit event,
and inhibits its own transmissions for the
duration of the Multi-Transmit event, plus a
random number of delay slots between 0 and (RN-1). If the local RN parameter is zero, the delay
is only for the calculated duration of the Multi-Transmit event. Thus, an RX module need only
receive one of the transmissions, and it will keep off the channel until the TX module is done. If
follow-on packets are coming, the RX modules will move to the new frequency and listen for the
follow-on packet for a specific period of time.
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XTend™ RF Module - Product Manual
Repeater Mode
Attributes:Low power consumption
Minimized interference
Each RF packet is tagged with a unique Packet ID (PID).
Each repeater will repeat a packet only once (tracked by the PID).
Increased latency and decreased throughput
(Latency and throughput is determined by number of hops, not by number of
repeaters. Multiple repeaters within range of source node count as one hop.)
All RF packets propagate to every module in the network (filtering rules apply).
Packet destination addresses (DT) determine which packets are sent out serial
port and/or retransmitted.
Broadcast communications - each packet comes out every node exactly once.
Addressed communications - all modules see every packet. Only the module
with a matching address will forward it to the DO buffer (UART IN).
Constraints:Requires that each module have a unique MY (Source Address) parameter.
System must introduce just one packet at a time to the network for transmission
(Maximum number of bytes is determined by the PK parameter).
Each hop (H) decreases network throughput by a factor of 1/(H+1). Additional
repeaters add network redundancy without decreasing throughput.
Suggestions:Insert a variable delay before repeating packets to avoid collisions
(based on RSSI).
Buffer any incoming serial data and delay response packet transmissions until
previous packet has cleared out of network.
For best results, use the RO and RB commands to ensure that the RF packets
align with the underlying protocol packets as the network can only accept one RF
packet at a time.
Required Parameter Values (TX module): MD = 5 or 6, MY = unique value (can be accomplished by issuing the AM (Auto-set MY) and WR (Write) commands to all modules in the network)
Related Commands: Networking (MD, DT, MY, AM), Serial Interfacing (RN, PK, RO, RB)
Recommended Use: Use in networks where intermediary modules are needed to relay data to
modules beyond the transmission range of the base module.
Theory of Operation
Integrators can extend the effective range and reliability of their data radio system by forwarding
traffic through one or more repeaters. Instead of using routing tables and path discovery to
establish dynamic paths through a network, the repeater system uses a sophisticated algorithm to
propagate each RF packet through the entire network.
The network supports RF packets up to 2048 bytes (when the RF data rate is set at 9600 bps (BR
= 0)). The repeater network can operate using broadcast or addressed communications for multidrop networks and works well in many systems with no special configuration.
When in Repeater Mode, the network repeats each message among all available modules exactly
one time. This mechanism eliminates the need for configuring specific routes.
Figure 4-06. Repeater Network Topology
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Repeater Network Configuration
A network may consist of End Nodes (EN), End/Repeater Nodes (ERN) and a Base Node (BN). The
base node initiates all communications.
A repeater network can be configured to operate using Basic Broadcast or Basic Addressed
communications. The addressing capabilities of the module allow integrators to send a packet as a
global packet (DT = 0xFFFF) and shift out of every module in the network (Basic Broadcast).
Alternatively, the packet can be sent with a specific DT (Destination Address) parameter so that it
is only accepted by a specific remote node (Basic Addressed).
Configuration Instruction (Basic Broadcast Communications)
Assign each module a unique MY (source) address. (The AM (Auto-set MY) command will configure a unique source address that is based on module serial number.)
Enable Basic Broadcast Communications (DT = 0xFFFF) or Addressed Broadcast Communications (DT specifies a specific destination)
Configure PK, RO and RB to ensure that RF packet aligns with protocol packet. (ex. PK=0x100,
RB=0x100, RO depends on baud rate).
Configure one or more repeaters in the system (MD = 5).
Configure remote nodes as destinations (MD = 6). This will ensure that the remote node waits
for the repeater traffic to subside before it transmits a response.
The configuration instructions above reflect configuration for a Basic Broadcast Repeater system.
To configure a Basic Addressed Repeater system, use the DT (Destination Address) parameter to
assign unique addresses to each module in the network.
Algorithm Details
• Packet ID (PID) is composed of TX (transmitting) module MY address and packet sequence
number.
• Incoming packets with a PID already found in the PID buffer will be ignored.
• Each module maintains a PID buffer 4 deep of previously received packets (managed as
FIFO).
Packets may be shifted out the serial port and/or repeated depending on the DT parameter
contained in the RF packet.
Table 4-02.
DT (Destination Address) parameter truth table
Address Match
Send out serial port?
Repeat?
Global
Yes
Yes
Local
Yes
No
None
No
Yes
Repeat Delay Based on RSSI
A transmitted packet may be received by more that one repeater at the same time. In order to
reduce the probability that the repeaters will transmit at the same instant, resulting in a collision
and possible data loss; an algorithm has been developed that will allow a variable back-off prior to
retransmission of the packet by a repeater. The algorithm allows radios that receive the packet
with a stronger RF signal (RSSI) to have the first opportunity to retransmit the packet.
The RN (Delay Slots) parameter is used to configure this delay. Set RN=0 (no delays) for small
networks with few repeaters or repeaters that are not within range of each other. Set RN=1 for
systems with 2 to 5 repeaters that may be within range of each other.
The actual length of the delay is computed by the formula:
Delay (ms) = L * DS
DS = (-41-RSSI)/10*RN)+RandomInt(0,RN)
Where L is the length of the transmitted packet in milliseconds, DS is the number of delay slots to
wait, RSSI is the received signal strength in dBm, RN is the value of the RN register and
RandomInt(A,B) is a function that returns a random integer from A to B-0
Response Packet Delay
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XTend™ RF Module - Product Manual
As a packet propagates through the repeater network, if any node receives the data and generates
a quick response, the response needs to be delayed so as not to collide with subsequent
retransmissions of the original packet. To reduce collisions, both repeater and end node radios in a
repeater network will delay transmission of data shifted in the serial port to allow any repeaters
within range to complete their retransmissions.
The time for this delay is computed by the formula:
Maximum Delay (ms) = L * DS
DS = ((-41-(-100))/10)*RN)+RN+1
Where L is the length of the transmitted packet in milliseconds, DS is the number of delay slots to
wait, RSSI is the received signal strength in dBm, and RN is the value of the RN register.
Use Case - Broadcast Repeater Network
Consider modules R1 through R10 each communicating to a PLC using the ModBus protocol and
spaced evenly in a line. All ten modules are configured as 'destinations & repeaters' within the
scope of Basic Broadcast Communications (MD=5, AM, DT=0xFFFF, PK=0x100, RO=0x03,
RB=0x100, RN=1). The Base Host (BH) shifts payload that is destined for R10 to R1. R1 initializes
RF communication and transmits payload to nodes R2 through R5 which are all within range of R1.
The modules R2 through R5 receive the RF packet and retransmit the packet simultaneously. They
also send the data out the serial ports, to the PLCs.
Table 4-03.
Commands used to configure repeater functions
AT
Command
Binary
Command
AT Command
Name
AM
0x3A (58d)
Auto-set MY
DT
0x00 (0d)
Destination Address
0 - 0xFFFF
MD
0x3C (60d)
RF Mode
0-6
MY
0x2A (42d)
Source Address
0 - 0xFFFF
0xFFFF
RN
0x19 (25d)
Delay Slots
0 - 0xFF [slots]
WR
0x08 (8d)
Write
Range
# Bytes
Returned
Factory
Default
Bandwidth Considerations
Using broadcast repeaters in a network reduces the overall network data throughput as each
repeater must buffer an entire packet before retransmitting it. For example: if the destination is
within range of the transmitter and the packet is 32-bytes long, the transmission will take 12ms on
an XTend module operating at 115,200 baud. If the same packet must propagate through two
repeaters, it will take 12ms to arrive at the first repeater, 12ms to get to the second and a final
12ms to reach the destination for a total of 36ms. Taking into account UART transfer times (~1ms/
byte at 9600 baud), a server to send a 32-byte query and receive a 32-byte response is about
200ms, allowing for 5 polls per second. With the two repeaters in the path, the same query/
response sequence would take about 500ms for 2 polls per second.
Generally, network throughput will decrease by a factor of 1/(R+1), with R representing the
number of repeaters between the source and destination.
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XTend™ RF Module - Product Manual
Polling Mode (Basic)
NOTE: Polling Mode (Basic) and Polling Mode (Acknowledged) [p53] operate in the same way. The
only difference between the two modes is in their means of achieving reliable delivery of data. In
Polling Mode (Basic), reliable delivery is achieved using multiple transmissions.
Attributes:Utilizes high percentage of available network bandwidth
Eliminates collisions
Works with reliable delivery (RR or MT parameters)
Supports binary data transfers
Base module requests packets from remote module by polling a sequential
range of addresses
Base module is configured to specify the range of addresses being polled
Uses inter-character delay to create RF packet lengths aligned with protocol
packet lengths up to 2048 bytes long.
Required Parameter Values (Base): MD (RF Mode) = 3, PB (Polling Begin Address), PE (Polling
End Address)
Required Parameter Value (Remote): MD (RF Mode) = 4
Related Commands: Networking (MT, PD, DT, MY, AM)
Constraints: The minimum time interval between polling cycles is configurable. However, if the
remote modules cannot all be processed within that time interval, the polling cycle is ineffective
(i.e. it will impose no additional delay). In order to ensure a pause between polling cycles, PD
must be set to a value which is large enough to accommodate the pause.
Recommended Use: Use for point-to-multipoint applications that require Reliable Delivery of
data. Use this mode when it is critical that a base module be able to discern data coming from
multiple modules.
Theory of Operation
A ‘Polling Base’ module will cycle through a sequential range of addresses. The ‘Polling Base’ will
poll each ‘Polling Remote’ module, wait for a response, then poll the next remote address in the
sequence. Each ‘Polling Remote’ will respond by sending the data from its DI (Data In) buffer
following the RB (Packetization Threshold) & RO (Packetization Timeout) parameters. When there
is no eligible data to send, the ‘Polling Remote’ will not respond. The ‘Polling Base’ will poll the next
address in the polling sequence after a short delay.
Polling Base Configuration:
Set the MD (RF Mode) parameter (MD = 3).
Set MY (Source Address) parameter (MY = 0).
Set the sequential range of Polling Addresses using the PB (Polling Begin Address) and PE
(Polling End Address) parameters.
(Optional) Enable Basic Reliable Delivery (MT >= 0). Note: Acknowledged Reliable Delivery is
also supported. Refer to the ‘Polling Mode - Acknowledged’ section for more information.
(Optional) Use the PD (Minimum Polling Delay) command to configure a delay between polls to
slow down system (if needed).
(Optional) Enable API Mode to address remotes within polling range on a packet-by-packet
basis.
Polling Remote Configuration:
Set the MD (RF Mode) parameter (MD = 4).
Configure sequential source addresses for all remote modules using the MY (Source Address)
command.
Set the DT (Destination Address) parameter to point to ‘Polling Base’ (DT = 0x0000).
(Optional) Enable Basic Reliable Delivery (MT >= 0). Note: Acknowledged Reliable Delivery is
also supported. Refer to the ‘Polling Mode - Acknowledged’ section for more information.
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Acknowledged Communications
Acknowledged Mode
Attributes:Reliable delivery through positive acknowledgements for each packet
Throughput, latency and jitter vary depending on the quality of the channel and
the strength of the signal.
Required Parameter Values (TX module): RR (Retries) >= 1
Related Commands: Networking (DT, MK, RR), Serial Interfacing (PK, RN, RO, RB, TT)
Recommended Use: Use for applications that require Reliable Delivery. If messages are smaller
than 256 bytes, use RB and RO commands to align RF packets to application packets.
Connection Sequence
Figure 4-07. Acknowledged Mode State
Diagram (TX module)
After sending a packet while in
Acknowledged Mode, the TX
(transmitting) module listens for an
ACK (acknowledgement). If it
receives the ACK, it will either move
on to sending a subsequent packet
(if more transmit data is pending) or
will wait for exactly RN random delay
slots before allowing another
transmission (if no more data is
pending to be transmitted).
If the TX module does not receive
the ACK within the allotted time, it
will retransmit the packet with a new
RF initializer following the ACK slot.
There is no delay between the first
ACK slot and the first retransmission.
Subsequent retransmissions incur a
delay of a random number of delay
slots, between 0 and RN. If RN is set
to 0 on the TX module, there are
never any back-off delays between
retransmissions. Note that during
back-off delays, the TX module will
go into Idle Mode and may receive
RF data. This can have the effect of
increasing the back-off delay, as the
module cannot return to Transmit (or
retransmit) Mode as long as it is receiving RF data.
After receiving and acknowledging a packet, the RX (receiving) module will move to the next
frequency and listen for either a retransmission or new data for a specific period of time. Even if
the TX module has indicated that it has no more pending transmit data, it may not have received
the previous ACK, and so may retransmit the packet, possibly with no delay after the ACK slot. In
this case, the RX module will always detect the immediate retransmission, which will hold off the
communications channel and thereby reduce collisions. RX modules acknowledge each
retransmission they receive, but they only pass the first copy of a packet they receive out the
UART.
RB and RO parameters are not applied to subsequent packets, meaning that once transmission
has begun, it will continue uninterrupted until the DI buffer is empty or the streaming limit (TT
parameter) has been reached. As with the first packet, the payload of each subsequent packet
includes up to the maximum packet size (PK parameter), and the TX module checks for more
pending data near the end of each packet.
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The TT parameter (streaming limit) specifies the maximum number of bytes that the TX module
will send in one transmission event, which may consist of many packets and retries. If the TT
parameter is reached, the TX module will force a random delay of 1 to RN delay slots (exactly 1
delay slot if RN is zero). Each packet is counted only once toward TT, no matter how many times
the packet is retransmitted.
Subsequent packets in Acknowledged Mode are similar to those in Streaming Mode, with the
addition of an ACK between each packet, and the possibility of retransmissions. Subsequent
packets are sent without an RF initializer, as the RX modules are already synchronized to the TX
module from the preceding packet(s) and they remain synchronized for the duration of the
transmission event. Each retransmission of a packet includes an RF initializer.
Once the TX module has sent all pending data or has reached the TT limit, the acknowledged
transmission event is completed. The TX module will not transmit again for exactly RN delay slots,
if the local RN parameter is set to a non-zero value. The RX module will not transmit for a random
number of delay slots between 0 and (RN-1), if the local RN parameter is set to a non-zero value.
These delays are intended to lessen congestion following long bursts of packets from a single TX
module, during which several RX modules may have themselves become ready to transmit.
Polling Mode (Acknowledged)
NOTE: Polling Mode (Acknowledged) and Polling Mode (Basic) [p50] operate in the same way. The
difference between the two modes is in their means of achieving reliable delivery of data. In Polling Mode (Acknowledged), reliable delivery is achieved using retries and acknowledgements.
Attributes:Utilizes high percentage of available network bandwidth
Eliminates collisions
Works with reliable delivery (RR or MT parameters)
Supports binary data transfers
Base module requests packets from remote module by polling a sequential
range of addresses
Base module is configured to specify the range of addresses being polled
Uses inter-character delay to create RF packet lengths aligned with protocol
packet lengths up to 2048 bytes long.
Required Parameter Values (Base): MD (RF Mode) = 3, PB (Polling Begin Address), PE (Polling
End Address)
Required Parameter Values (Remote): MD (RF Mode) = 4
Related Commands: Networking (RR, PD, DT, MY, AM)
Constraints: The minimum time interval between polling cycles is configurable. However, if the
remote modules cannot all be processed within that time interval, the polling cycle is ineffective
(i.e. it will impose no additional delay). In order to ensure a pause between polling cycles, PD
must be set to a value which is large enough to accommodate the pause.
Recommended Use: Use for point-to-multipoint applications that require Reliable Delivery of
data. Use this mode when it is critical that a base module be able to discern data coming from
multiple modules.
Theory of Operation
A ‘Polling Base’ module will cycle through a sequential range of addresses. The ‘Polling Base’ will
poll each ‘Polling Remote’ module, wait for a response, then poll the next remote address in the
sequence. Each ‘Polling Remote’ will respond by sending the data from its DI (Data In) buffer
following the RB (Packetization Threshold) & RO (Packetization Timeout) parameters. When there
is no eligible data to send, the ‘Polling Remote’ will not respond. The ‘Polling Base’ will poll the next
address in the polling sequence after a short delay.
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Polling Base Configuration:
Set the MD (RF Mode) parameter (MD = 3).
Set MY (Source Address) parameter (MY = 0).
Set the sequential range of Polling Addresses using the PB (Polling Begin Address) and PE
(Polling End Address) parameters.
(Optional) Enable Acknowledged Reliable Delivery (RR >= 0). Note: Basic Reliable Delivery is
also supported. Refer to the ‘Polling Mode - Basic section for more information.
(Optional) Use the PD (Minimum Polling Delay) command to configure a delay between polls to
slow down system (if needed).
(Optional) Enable API Mode to address remotes within polling range on a packet-by-packet
basis.
Polling Remote Configuration:
Set the MD (RF Mode) parameter (MD = 4).
Configure sequential source addresses for all remote modules using the MY (Source Address)
command.
Set the DT (Destination Address) parameter to point to ‘Polling Base’ (DT = 0x0000).
(Optional) Enable Acknowledged Reliable Delivery (RR >= 0). Note: Basic Reliable Delivery is
also supported. Refer to the ‘Polling Mode - Basic section for more information.
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Appendix A: Agency Certifications
FCC (United States) Certification
The XTend RF Module complies with Part 15 of the FCC rules and regulations. Compliance with the
labeling requirements, FCC notices and antenna usage guidelines is required.
In order to operate under Digi’s FCC Certification, integrators must comply with the following
regulations:
1.
The integrator must ensure that the text provided with this device [Figure A-01] is placed
on the outside of the final product and within the final product operation manual.
2.
The XTend RF Module may only be used with antennas that have been tested and approved
for use with this module [refer to ‘FCC-approved Antennas’ section].
Integrator Labeling Requirements
WARNING: The Original Equipment Manufacturer (OEM) must ensure that FCC labeling
requirements are met. This includes a clearly visible label on the outside of the final
product enclosure that displays the text shown in the figure below.
Figure A-01. Required FCC Label for OEM products containing the XTend RF Module
Contains FCC ID: MCQ-9XTENDB
The enclosed device complies with Part 15 of the FCC Rules. Operation is subject to the following two
conditions: (i.) this device may not cause harmful interference and (ii.) this device must accept any interference received, including interference that may cause undesired operation.
FCC Notices
IMPORTANT: The XTend RF Module has been certified by the FCC for use with other products
without any further certification (as per FCC section 2.1091). Modifications not expressly approved
by Digi could void the user’s authority to operate the equipment.
IMPORTANT: Integrators must test final product to comply with unintentional radiators (FCC
sections 15.107 & 15.109) before declaring compliance of their final product to Part 15 of the FCC
rules.
IMPORTANT: The RF module has been certified for remote and base radio applications. If the
module will be used for portable applications, the device must undergo SAR testing.
This equipment has been tested and found to comply with the limits for a Class B digital device,
pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection
against harmful interference in a residential installation. This equipment generates, uses and can
radiate radio frequency energy and, if not installed and used in accordance with the instructions,
may cause harmful interference to radio communications. However, there is no guarantee that
interference will not occur in a particular installation.
If this equipment does cause harmful interference to radio or television reception, which can be
determined by turning the equipment off and on, the user is encouraged to try to correct the
interference by one or more of the following measures: Re-orient or relocate the receiving
antenna, Increase the separation between the equipment and receiver, Connect equipment and
receiver to outlets on different circuits, or Consult the dealer or an experienced radio/TV technician
for help.
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XTend™ RF Module - Product Manual
Limited Modular Approval
Power output is conducted at the antenna terminal and can be adjusted from 1 milliwatt to 1 Watt
at the integrator level. This is an RF module approved for limited modular use operating as a
mobile transmitting device with respect to Section 2.1091 and is limited to integrator installation
for mobile and fixed applications only. During final installation, end users are prohibited from
access to any programming parameters. Professional installation adjustment is required for setting
module power and antenna gain to meet EIRP compliance for high gain antenna(s).
Final antenna installation and operating configurations of this transmitter including antenna gain
and cable loss must not exceed the EIRP of the configuration used for calculating MPE. Grantee
(Digi) must coordinate with integrators to ensure the end users and installers of products
operating with the module are provided with operating instructions to satisfy RF exposure
requirements.
The FCC grant is valid only when the device is sold to integrators. Integrators are instructed to
ensure the end user has no manual instructions to remove, adjust or install the device.
FCC-approved Antennas
WARNING: This device has been tested with Reverse Polarity SMA connectors with the antennas listed in the
tables of this section. When integrated into products, fixed antennas require installation preventing end users from
replacing them with non-approved antennas. Antennas not listed in the tables must be tested to comply with FCC
Section 15.203 (unique antenna connectors) and Section 15.247 (emissions).
Fixed Base Station and Mobile Applications
Digi RF Modules are pre-FCC approved for use in fixed base station and mobile applications. When
the antenna is mounted at least 20cm (8") from nearby persons, the application is considered a
mobile application.
Portable Applications and SAR Testing
When the antenna is mounted closer than 20cm to nearby persons, then the application is
considered "portable" and requires an additional test be performed on the final product. This test
is called Specific Absorption Rate (SAR) testing and measures the emissions from the module and
how they affect the person.
RF Exposure
This statement must be included as a CAUTION statement in integrator product manuals.
WARNING: This equipment is approved only for mobile and base station transmitting
devices. Antenna(s) used for this transmitter must be installed to provide a separation
distance of at least 30 cm from all persons and must not be co-located or operating in
conjunction with any other antenna or transmitter.
NOTE: The separation distance indicated in the above is 30 cm, but any distance greater than or
equal to 23 cm can be used (per MPE evaluation).
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XTend™ RF Module - Product Manual
Antenna Options (1-watt transmit power output or lower)
The antennas in the tables below have been approved for use with this module. Digi does not carry all of these antenna
variants. Contact Digi Sales for available antennas.
Half-wave antennas (approved when operating at 1-watt power output or lower)
Part Number
A09-HSM-7
A09-HASM-675
A09-HABMM-P6I
A09-HABMM-6-P6I
A09-HBMM-P6I
A09-HRSM
A09-HASM-7
A09-HG
A09-HATM
A09-H
Type
Straight half-wave
Articulated half-wave
Articulated half-wave w/ 6" pigtail
Articulated half-wave w/ 6" pigtail
Straight half-wave w/ 6" pigtail
Right angle half-wave
Articulated half-wave
Glass mounted half-wave
Articulated half-wave
Half-wave dipole
Connector
RPSMA
RPSMA
MMCX
MMCX
MMCX
RPSMA
RPSMA
RPSMA
RPTNC
RPSMA
Gain
3.0 dBi
2.1 dBi
2.1 dBi
2.1 dBi
2.1 dBi
2.1 dBi
2.1 dBi
2.1 dBi
2.1 dBi
2.1 dBi
Application
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed
Fixed
Fixed
Fixed
Fixed
Yagi antennas (approved when operating at 1-watt power output or lower)
Part Number
A09-Y6
A09-Y7
A09-Y8
A09-Y9
A09-Y10
A09-Y11
A09-Y12
A09-Y13
A09-Y14
A09-Y14
A09-Y15
A09-Y15
A09-Y6TM
A09-Y7TM
A09-Y8TM
A09-Y9TM
A09-Y10TM
A09-Y11TM
A09-Y12TM
A09-Y13TM
A09-Y14TM
A09-Y14TM
A09-Y15TM
A09-Y15TM
Type
2 Element Yagi
3 Element Yagi
4 Element Yagi
4 Element Yagi
5 Element Yagi
6 Element Yagi
7 Element Yagi
9 Element Yagi
10 Element Yagi
12 Element Yagi
13 Element Yagi
15 Element Yagi
2 Element Yagi
3 Element Yagi
4 Element Yagi
4 Element Yagi
5 Element Yagi
6 Element Yagi
7 Element Yagi
9 Element Yagi
10 Element Yagi
12 Element Yagi
13 Element Yagi
15 Element Yagi
Connector
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
Gain
6.1 dBi
7.1 dBi
8.1 dBi
9.1 dBi
10.1 dBi
11.1 dBi
12.1 dBi
13.1 dBi
14.1 dBi
14.1 dBi
15.1 dBi
15.1 dBi
6.1 dBi
7.1 dBi
8.1 dBi
9.1 dBi
10.1 dBi
11.1 dBi
12.1 dBi
13.1 dBi
14.1 dBi
14.1 dBi
15.1 dBi
15.1 dBi
Required Antenna Cable Loss
1.7 dB
2.7 dB
3.7 dB
4.7 dB
5.7 dB
6.7 dB
7.7 dB
8.7 dB
9.7 dB
9.7 dB
10.7 dB
10.7 dB
1.7 dB
2.7 dB
3.7 dB
4.7 dB
5.7 dB
6.7 dB
7.7 dB
8.7 dB
9.7 dB
9.7 dB
10.7 dB
10.7 dB
Application
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Omni-directional base station antennas (approved when operating at 1-watt power output or lower)
Part Number
A09-F0
A09-F1
A09-F2
A09-F3
A09-F4
A09-F5
A09-F6
A09-F7
A09-F8
A09-W7
A09-F0
A09-F1
A09-F2
A09-F3
A09-F4
A09-F5
A09-F6
Type
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Wire Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
© 2012 Digi Internatonal, Inc.
Connector
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPSMA
RPSMA
RPSMA
RPSMA
RPSMA
RPSMA
RPSMA
Gain
0 dBi
1.0 dBi
2.1 dBi
3.1 dBi
4.1 dBi
5.1 dBi
6.1 dBi
7.1 dBi
8.1 dBi
7.1 dBi
0 dBi
1.0 dBi
2.1 dBi
3.1 dBi
4.1 dBi
5.1 dBi
6.1 dBi
Required Antenna Cable Loss
0.1 dB*
1.1 dB*
2.1 dB*
1.1 dB*
0.1 dB*
Application
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
57
XTend™ RF Module - Product Manual
Omni-directional base station antennas (approved when operating at 1-watt power output or lower)
Part Number
A09-F7
A09-F8
A09-W7SM
A09-F0TM
A09-F1TM
A09-F2TM
A09-F3TM
A09-F4TM
A09-F5TM
A09-F6TM
A09-F7TM
A09-F8TM
A09-W7TM
Type
Fiberglass Base Station
Fiberglass Base Station
Wire Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Fiberglass Base Station
Wire Base Station
Connector
RPSMA
RPSMA
RPSMA
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
Gain
7.1 dBi
8.1 dBi
7.1 dBi
0 dBi
1.0 dBi
2.1 dBi
3.1 dBi
4.1 dBi
5.1 dBi
6.1 dBi
7.1 dBi
8.1 dBi
7.1 dBi
Required Antenna Cable Loss
1.1 dB*
2.1 dB*
1.1 dB*
0.1 dB*
1.1 dB*
2.1 dB*
1.1 dB*
Application
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
* FCC regulations stipulate a 36 dBm EIRP power requirement. Users implementing antenna gain greater than 6.0 dB must compensate for the
added gain with cable loss. When operating at 1 W power output, the sum (in dB) of cable loss and antenna gain shall not exceed 6.0 dB.
© 2012 Digi Internatonal, Inc.
58
XTend™ RF Module - Product Manual
Mag Mount antennas (approved when operating at 1-watt power output or lower)
Part Number
A09-M0SM
A09-M2SM
A09-M3SM
A09-M5SM
A09-M7SM
A09-M8SM
A09-M0TM
A09-M2TM
A09-M3TM
A09-M5TM
A09-M7TM
A09-M8TM
Type
Mag Mount
Mag Mount
Mag Mount
Mag Mount
Mag Mount
Mag Mount
Mag Mount
Mag Mount
Mag Mount
Mag Mount
Mag Mount
Mag Mount
Connector
RPSMA
RPSMA
RPSMA
RPSMA
RPSMA
RPSMA
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
Gain
0 dBi
2.1 dBi
3.1 dBi
5.1 dBi
7.1 dBi
8.1 dBi
0 dBi
2.1 dBi
3.1 dBi
5.1 dBi
7.1 dBi
8.1 dBi
Required Antenna Cable Loss
1.1 dB*
2.1 dB*
1.1 dB*
2.1 dB*
Application
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Multi-path antennas (approved when operating at 1-watt power output or lower)
Part Number
A09-DPSM-P12F
A09-D3NF-P12F
A09-D3SM-P12F
A09-D3PNF
A09-D3TM-P12F
A09-D3PTM
A92-D4PNF
A92-D4P
A92-D4PTM
Type
omni directional permanent mount w/ 12ft pigtail
omni directional magnetic mount w/ 12ft pigtail
omni directional w/ 12ft pigtail
omni directional permanent mount
omni directional w/ 12ft pigtail
omni directional permanent mount
900 MHz / 2.4GHz permanent mount
900 MHz / 2.4GHz permanent mount
900 MHz / 2.4GHz permanent mount
Connector
RPSMA
RPN
RPSMA
RPN
RPTNC
RPTNC
RPN
RPSMA
RPTNC
Gain
3.0 dBi
3.0 dBi
3.0 dBi
3.0 dBi
3.0 dBi
3.0 dBi
2.1 dBi
2.1 dBi
2.1 dBi
Application
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
Fixed
* FCC regulations stipulate a 36 dBm EIRP power requirement. Users implementing antenna gain greater than 6.0 dB must compensate for the
added gain with cable loss. When operating at 1 W power output, the sum (in dB) of cable loss and antenna gain shall not exceed 6.0 dB.
Antenna Options (100 mW transmit power output or lower)
Half-wave antennas (approved when operating at 100 mW power output or lower)
Part Number
A09-QW
A09-QRAMM
A09-QSM-3
A09-QSM-3H
A09-QBMM-P6I
A09-QHRN
A09-QHSN
A09-QHSM-2
A09-QHRSM-2
A09-QHRSM-170
A09-QRSM-380
A09-QAPM-520
A09-QSPM-3
A09-QAPM-3
A09-QAPM-3H
© 2012 Digi Internatonal, Inc.
Type
Quarter-wave wire
3 " Quarter-wave wire
Quarter-wave straight
Heavy duty quarter-wave straight
Quarter-wave w/ 6" pigtail
Miniature Helical Right Angle solder
Miniature Helical Right Angle solder
2" Straight
2" Right angle
1.7" Right angle
3.8" Right angle
5.2" Articulated Screw mount
3" Straight screw mount
3" Articulated screw mount
3" Articulated screw mount
Connector
Permanent
MMCX
RPSMA
RPSMA
MMCX
Permanent
Permanent
RPSMA
RPSMA
RPSMA
RPSMA
Permanent
Permanent
Permanent
Permanent
Gain
1.9 dBi
2.1 dBi
1.9 dBi
1.9 dBi
1.9 dBi
-1 dBi
-1 dBi
1.9 dBi
1.9 dBi
1.9 dBi
1.9 dBi
1.9 dBi
1.9 dBi
1.9 dBi
1.9 dBi
Application
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
59
XTend™ RF Module - Product Manual
Yagi antennas (approved when operating at 100 mW power output or lower)
Part Number
Type
Connector
Gain
A09-Y6
A09-Y7
A09-Y8
A09-Y9
A09-Y10
A09-Y11
A09-Y12
A09-Y13
A09-Y14
A09-Y14
A09-Y15
A09-Y15
A09-Y6TM
A09-Y7TM
A09-Y8TM
A09-Y9TM
A09-Y10TM
A09-Y11TM
A09-Y12TM
A09-Y13TM
A09-Y14TM
A09-Y14TM
A09-Y15TM
A09-Y15TM
2 Element Yagi
3 Element Yagi
4 Element Yagi
4 Element Yagi
5 Element Yagi
6 Element Yagi
7 Element Yagi
9 Element Yagi
10 Element Yagi
12 Element Yagi
13 Element Yagi
15 Element Yagi
2 Element Yagi
3 Element Yagi
4 Element Yagi
4 Element Yagi
5 Element Yagi
6 Element Yagi
7 Element Yagi
9 Element Yagi
10 Element Yagi
12 Element Yagi
13 Element Yagi
15 Element Yagi
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPN
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
RPTNC
6.1 dBi
7.1 dBi
8.1 dBi
9.1 dBi
10.1 dBi
11.1 dBi
12.1 dBi
13.1 dBi
14.1 dBi
14.1 dBi
15.1 dBi
15.1 dBi
6.1 dBi
7.1 dBi
8.1 dBi
9.1 dBi
10.1 dBi
11.1 dBi
12.1 dBi
13.1 dBi
14.1 dBi
14.1 dBi
15.1 dBi
15.1 dBi
Required Antenna
Cable Loss
1 dB
2 dB
3 dB
3 dB
4 dB
4 dB
1 dB
2 dB
3 dB
3 dB
4 dB
4 dB
Application
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
Fixed / Mobile
IC (Industry Canada) Certification
This device complies with Industry Canada license-exempt RSS standard(s). Operation is subject
to the following two conditions: (1) this device may not cause interference, and (2) this device
must accept any interference, including interference that may cause undesired operation of the
device.
Le présent appareil est conforme aux CNR d'Industrie Canada applicables aux appareils radio
exempts de licence. L'exploitation est autorisée aux deux conditions suivantes : (1) l'appareil ne
doit pas produire de brouillage, et (2) l'utilisateur de l'appareil doit accepter tout brouillage
radioélectrique subi, même si le brouillage est susceptible d'en compromettre le fonctionnement.
Labeling Requirements
Labeling requirements for Industry Canada are similar to those of the FCC. A clearly visible label
on the outside of the final product must display the following text:
Contains Model XT09B Radio, IC: 1846A-9XTENDB
The integrator is responsible for its product to comply with IC ICES-003 and FCC Part 15, Sub. B Unintentional Radiators. ICES-003 is the same as FCC Part 15 Sub. B and Industry Canada
accepts FCC test report or CISPR 22 test report for compliance with ICES-003.
Transmitters for Detachable Antennas
This radio transmitter has been approved by Industry Canada to operate with the antenna types
listed in the table above with the maximum permissible gain and required antenna impedance for
each antenna type indicated. Antenna types not included in this list, having a gain greater than the
maximum gain indicated for that type, are strictly prohibited for use with this device. The required
antenna impedance is 50 ohms.
Le présent émetteur radio a été approuvé par Industrie Canada pour fonctionner avec les types
d'antenne énumérés ci-dessous et ayant un gain admissible maximal et l'impédance requise pour
chaque type d'antenne. Les types d'antenne non inclus dans cette liste, ou dont le gain est
supérieur au gain maximal indiqué, sont strictement interdits pour l'exploitation de l'émetteur.
© 2012 Digi Internatonal, Inc.
60
XTend™ RF Module - Product Manual
Detachable Antennas
Under Industry Canada regulations, this radio transmitter may only operate using an antenna of a
type and maximum (or lesser) gain approved for the transmitter by Industry Canada. To reduce
potential radio interference to other users, the antenna type and its gain should be so chosen that
the equivalent isotropically radiated power (e.i.r.p.) is not more than that necessary for successful
communication.
Conformément à la réglementation d'Industrie Canada, le présent émetteur radio peut fonctionner
avec une antenne d'un type et d'un gain maximal (ou inférieur) approuvé pour l'émetteur par
Industrie Canada. Dans le but de réduire les risques de brouillage radioélectrique à l'intention des
autres utilisateurs, il faut choisir le type d'antenne et son gain de sorte que la puissance isotrope
rayonnée équivalente (p.i.r.e.) ne dépasse pas l'intensité nécessaire àl'établissement d'une
communication satisfaisante.
C-TICK (Australia) Certification
Power Requirements
Regulations in Australia stipulate a maximum of 30 dBm EIRP (Effective Isotropic Radiated Power).
The EIRP equals the sum (in dBm) of power output, antenna gain and cable loss and cannot not
exceed 30 dBm.
Figure A-02. EIRP Formula for Australia
NOTE: The maximum EIRP for the FCC (United States) and IC (Canada) is 36 dBm.
These modules comply with requirements to be used in end products in Australia. All products
with EMC and radio communications must have a registered C-Tick mark. Registration to use the
compliance mark will only be accepted from Australian manufacturers or importers, or their agent,
in Australia. In order to have a C-Tick mark on an end product, a company must comply with a or
b below:
a)
have a company presence in Australia.
b)
have a company/distributor/agent in Australia that will sponsor the import of the end product.
Contact Digi for questions related to locating a contact in Australia.
© 2012 Digi Internatonal, Inc.
61
Appendix B: Development Guide
Development Kit Contents
The XTend Development Kit includes the hardware and software needed to rapidly create long
range wireless links between devices.
Table B-01. XTend Development Kit Contents
Description
Part Number
XTend RF Module
Item
Qty.
Long Range 900 MHz RF Module (w/ RPSMA Connector)
XT09-SI
XTend RF Module
Long Range 900 MHz RF Module (w/ MMCX antenna)
XT09-MI
Antenna
900 MHz RPSMA, 6" Half-Wave, dipole, articulating, RPSMA
A09-HASM-675
Antenna
900 MHz RPSMA, 7" Half-Wave, dipole, articulating, w/ pigtail, MMCX
A09-HABMM-P5I
RS-232 Interface Board
Enables communication to RS-232 devices
XTIB-R
RS-232 Cable (6')
Connects interface board to devices having an RS-232 serial port
JD2D3-CDS-6F
Serial Loopback Adapter
Connects to the female RS-232 (DB-9) serial connector of the Digi
Interface Board and can be used to configure the module to function as
a repeater (for range testing)
JD2D3-CDL-A
NULL Modem Adapter
(male-to-male)
Connects to the female RS-232 (DB-9) serial connector of the Digi
Interface Board and can be used to connect the module to another
DCE (female DB9) device
JD2D2-CDN-A
NULL Modem Adapter
(female-to-female)
Used to bypass radios to verify serial cabling is functioning properly
JD3D3-CDN-A
Male DB-9 to RJ-45
Adapter
Facilitates adapting the DB-9 Connector of the Digi Interface Board to a
CAT5 cable (male DB9 to female RJ45)
JE1D2-CDA-A
Female DB-9 to RJ-45
Adapter
Facilitates adapting the DB-9 Connector of the Digi Interface Board to a
CAT5 cable (female DB9 to female RJ45)
JE1D3-CDA-A
Power Adapter
Allows Interface Board to be powered by a 110 Volt AC power supply
(not included with international (-INT) development kits)
JP4P2-9V10-6F
CD
Contains documentation, software and tools needed for RF operation.
MD0010
Quick Start Guide
Familiarizes users with some of the module's most important functions.
MD0016
Interfacing Hardware
The XTend Development Kit includes a pair of RS-232 interface boards that supports the RS-232/
485/422 protocols. When the modules are mounted to the interface boards, the boards provide
the following development tools:
• Fast and direct connection to serial devices (such as PCs) and therefore easy access to the
module registries - The parameters stored in the registry allow integrators to customize the
modules to suite the specific needs of their data systems.
• External DIP switch for automatic configuration of commonly used module profiles
• Conversion of signals between TTL levels and RS-232 levels
The Digi Interface board provides means for connecting the module to any device that has an
available RS-232 or RS-485/422 connection. The following sections illustrate how to use the
interface boards for development purposes.
Note: In the sections the follow, an RF module mounted to an interface board will be referred to as a
"Module Assembly".
© 2012 Digi International Inc.
62
XTend™ RF Module - Product Manual
XTIB-R RS-232/485 Interface Board
B-01a. Config (Configuration) Switch
The Config Switch provides an alternate method for entering into
Command Mode. To enter Command Mode at the module's default RF
data rate, hold the Configuration Switch down for two seconds.
Figure B-01. Front View
B-01b. I/O & Power LEDs
The LEDs visualize gigantic status information and indicate module
activity as follows:
B-01c.
DB-9 Serial Port
B-01d
RSSI LEDs
Yellow (top LED) = Serial Data Out (to host)
Green (middle) = Serial Data In (from host)
Red (bottom)
= Power/TX Indicator (Red light is on when
powered; it pulses on/off briefly during RF transmission.))
B-01b.
I/O & Power LEDs
B-01e.
Power Connector
B-01a.
Config Switch
B-01c. DB-9 Serial Port
Standard female DB-9 (RS-232) connector. This connector can also
be used for RS-485 and RS-422 connections.
B-01d. RSSI LEDs
RSSI LEDs indicate the amount of fade margin present in an active
wireless link. Fade margin is defined as the difference between the
incoming signal strength and the module's receiver sensitivity.
LEDs ON
LEDs ON
LED ON
LED ON
Very Strong Signal (> 30 dB fade margin)
Strong Signal (> 20 dB fade margin)
Moderate Signal (> 10 dB fade margin)
Weak Signal (< 10 dB fade margin)
B-01e. Power Connector
7-28 VDC power connector (Center positive, 5.5/2.1mm)
Note: The XTIB-R interface board can accept voltages as low as 5V.
Contact Digi Technical Support to enable this option.
B-02a. DIP Switch
DIP Switch automatically configures the module to operate in
different modes during the power-on sequence. Each time the module
assembly (interface board + module) is powered-on, intelligence on
the board programs the attached module according to the positions of
the DIP Switch.
Figure B-02. Back View
B-02a.
DIP Switch
Figure B-03 illustrates DIP Switch settings. Table B-02 summarizes
the configurations triggered by the positions of the DIP Switch.
Figure B-03. DIP Switch Settings of the XTIB-R (RS-232/485) Interface Board
Refer to the tables in the ‘Automatic
DIP Switch Configurations’ section
[next page] regarding configurations triggered by the positions of
the DIP Switch (during power-up).
© 2012 Digi Internatonal, Inc.
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XTend™ RF Module - Product Manual
Automatic DIP Switch Configurations
Each time the module assembly is powered-on, AT commands are sent to the on-board RF module
as dictated by the positions of the DIP switches. DIP switch configurations are sent automatically
during the power-on sequence and affect module parameter values as shown in the table below.
Figure B-04. XTIB-R DIP Switch
Table B-02. Power-up Options - Commands sent to the module as result of DIP Switch Settings
(SW = DIP Switch)
Switches
Switches 1 & 2
(Restore Defaults /
Serial Interfacing)
Switches 5 & 6
(TX/RX Modes)
Condition
Behavior
Commands Sent During Power-up
If SW1 & SW2 are
ON (up)
Restore Defaults
ATRE
ATWR
(Restore Defaults)
(Write defaults to non-volatile memory)
If SW1 is ON (up)
RS-232 Operation
ATCS 0
(RS-232, CTS flow control)
If SW1 is OFF (down)
RS-485/422
Operation
ATCS 3
(RS-485 or RS-422 Operation)
If SW5 & SW6 are
OFF (down)
Multipoint Base
ATMY 0
ATDT FFFF
ATMT 3
(Source Address)
(Destination Address)
(Multi-Transmit option)
If SW5 is OFF (down)
& SW6 is ON (up)
Multipoint Remote
ATAM
ATDT 0
ATMT 0
ATRR A
(Auto-set MY, MY = unique)
(Destination Address)
(Multi-Transmit option)
(Retries)
If SW5 is ON (up) &
SW6 is OFF (down)
Point-to-Point
ATAM
ATDT FFFF
ATMT 3
(Auto-set MY, MY = unique)
(Destination Address)
(Multi-Transmit option)
If SW5 is ON (up) &
SW6 is ON (up)
User Defined
Processor is disabled and AT Commands are not sent to
the module (except for CS command as shown below.)
Table B-03. User Defined Mode (Switches 5 and 6 are ON (up))
Only DIP Switches ON (up)
SW1, SW5 and SW6
SW2, SW5 and SW6
SW5 and SW6 only
Condition
Command Sent During Power-up
If CS = 0, 1, 2 or 4
CS parameter remains the same
If CS = 3
ATCS 0
(RS-232 operation, CTS flow control)
If CS = 2
ATCS 2
(GPO1 high)
If CS = 0, 1, 3 or 4
ATCS 3
(RS-485/422 Operation)
If CS = 2
ATCS 2
(GPO1 high)
If CS = 0, 1, 3 or 4
ATCS 3
(RS-485/422 Operation)
Note: The results of SW 2, 5 & 6 ON and SW 5 & 6 ON are the same.
© 2012 Digi Internatonal, Inc.
64
XTend™ RF Module - Product Manual
Adapters
The development kit includes several adapters that facilitate the following functions:
• Performing Range Tests
• Testing Cables
• Connecting to other RS-232 DCE and DTE devices
• Connecting to terminal blocks or RJ-45 (for RS-485/422 devices)
NULL Modem Adapter (male-to-male)
Part Number: JD2D2-CDN-A (Black, DB-9 M-M) The male-to-male NULL modem adapter is
used to connect two DCE devices. A DCE device connects with a straight-through cable to the male
serial port of a computer (DTE).
Figure B-05. Male NULL modem adapter and pinouts
Figure B-06. Example of a Digi Radio Modem (DCE Device) connecting to another DCE device)
NULL Modem Adapter (female-to-female)
Part Number: JD3D3-CDN-A (Gray, DB-9 F-F) The female-to-female NULL modem adapter is
used to verify serial cabling is functioning properly. To test cables, insert the female-to-female
NULL modem adapter in place of a pair of module assemblies (RS-232 interface board + XTend RF
Module) and test the connection without modules in the connection.
Figure B-07. Female NULL modem adapter and pinouts
Serial Loopback Adapter
Part Number: JD2D3-CDL-A (Red, DB-9 M-F) The serial loopback adapter is used for range
testing. During a range test, the serial loopback adapter configures the module to function as a
repeater by looping serial data back into the radio for retransmission.
Figure B-08. Serial loopback adapter and pinouts
© 2012 Digi Internatonal, Inc.
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XTend™ RF Module - Product Manual
Male DB-9 to RJ-45 Adapter
Part Number: JD2D2-CDN-A (Yellow) This adapter facilitates adapting the DB-9 Connector of
the Digi Interface Board to a CAT5 cable (male DB9 to female RJ45).
Refer to the ‘RS-485 (4-wire) & RS-422 Operation’ sections for RS-485/422 connection guidelines.
Figure B-09. Male DB-9 to RJ-45 Adapter and pinouts
Female DB-9 to RJ-45 Adapter
Part Number: JD3D3-CDN-A (Green) This adapter Facilitates adapting the DB-9 Connector of
the Digi Interface Board to a CAT5 cable (female DB9 to female RJ45).
Refer to the ‘RS-485 (4-wire) & RS-422 Operation’ sections for RS-485/422 connection guidelines.
Figure B-10. Female DB-9 to RJ-45 Adapter and pinouts
© 2012 Digi Internatonal, Inc.
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XTend™ RF Module - Product Manual
Interfacing Protocols
The XTend Module Assembly (XTend RF Module mounted to the XTIB-R Interface Board) supports
the following interfacing protocols:
• RS-232
• RS-485 (2-wire) Half-Duplex
• RS-485 (4-wire) and RS-422
RS-232 Operation
DIP Switch Settings and Serial Port Connections
Figure B-11.
RS-232 DIP Switch Settings
Figure B-12.
Pins used on the female RS-232 (DB-9) Serial Connector
DIP Switch settings are read and applied
only while powering-on.
Table B-04. RS-232 Signals and their implementations on the XTend Module Assembly
(Low-asserted signals are distinguished by horizontal line over pin name.)
DB-9 Pin
RS-232
Name
X-CTU
Name*
Description
Implementation
DCD
GPO2
Data-Carrier-Detect
Connected to DSR (pin6 of DB-9)
RXD
DO
Received Data
Serial data exiting the module assembly (to host)
TXD
DI
Transmitted Data
Serial data entering into the module assembly (from host)
DTR
GPI2
Data-Terminal-Ready
Can enable Power-Down on the module assembly
GND
Ground Signal
Ground
DSR
GPO2
Data-Set-Ready
Connected to DCD (pin1 of DB-9)
RTS / CMD
GPI1
Request-to-Send /
Command Mode
Provides RTS flow control or enables Command Mode
CTS
GPO1
Clear-to-Send
Provides CTS flow control
RI
Ring Indicator
Optional power input that is connected internally to the
positive lead of the front power connector
* ‘X-CTU’ is software that can be used to configure the module. The software includes a naming convention
where "GPI" stands for ‘General Purpose Input’ and "GPO" for ‘General Purpose Output’.
© 2012 Digi Internatonal, Inc.
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XTend™ RF Module - Product Manual
Wiring Diagrams
Figure B-13. DTE Device (RS-232, male DB-9 connector) wired to a DCE Module Assembly (female DB-9)
Figure B-14. DCE Module Assembly (female DB-9 connector) wired to a DCE Device (RS-232, male DB-9)
Sample Wireless Connection: DTE <--> DCE
DCE <--> DCE
Figure B-15. Typical wireless link between DTE and DCE devices
© 2012 Digi Internatonal, Inc.
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XTend™ RF Module - Product Manual
RS-485 (2-wire) Operation
When operating within the RS-485 protocols, all communications are half-duplex.
DIP Switch Settings and Serial Port Connections
Figure B-16.
RS-485 (2-wire) Half-duplex
DIP Switch Settings
Figure B-17.
Pins used on the female RS-232 (DB-9)
Serial Connector
Figure B-18.
RS-485 (2-wire) w/ Termination (optional)
Termination is the 120 Ω resistor between T+ and T-.
DIP Switch settings are read and applied only while powering-on.
Note: Refer to Figures B-09 and B-10 for RJ-45 connector pin designations used in
RS-485/422 environments.
Table B-05. RS-485 (2-wire half-duplex) signals and their implementations on the XTend Module Assembly
DB-9 Pin
RS-485 Name
Description
Implementation
T/R- (TRA)
Negative Data Line
Transmit serial data to and from the XTend Module Assembly
GND
Ground Signal
Ground
T/R+ (TRB)
Positive Data Line
Transmit serial data to and from the XTend Module Assembly
PWR
Power
Optional power input that is connected internally
to the front power connector
1, 3, 4, 6, 7
not used
Wiring Diagram
Figure B-19. XTend Module Assembly in an RS-485 (2-wire) half-duplex environment
© 2012 Digi Internatonal, Inc.
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XTend™ RF Module - Product Manual
RS-485 (4-wire) & RS-422 Operation
DIP Switch Settings and Serial Port Connections
Figure B-20.
RS-485 (4-wire) & RS-422
DIP Switch Settings
Figure B-21.
Pins used on the female RS-232 (DB-9)
Serial Connector
Figure B-22.
RS-485 (4-wire)& RS-422 w/ Termination (optional)
Termination is the 120 Ω resistor between T+ and T-.
DIP Switch settings are read and applied only while powering-on.
Note: Refer to Figures B-09 and B-10 for RJ-45 connector pin designations used in
RS-485/422 environments.
Table B-06. RS-485/422 (4-wire) Signals and their implementations on the XTend Module Assembly
DB-9 Pin
RS-485/422
Name
Description
Implementation
T- (TA)
Transmit Negative
Data Line
Serial data sent from the XTend Module Assembly
R- (RA)
Receive Negative
Data Line
Serial data received by the XTend Module Assembly
GND
Signal Ground
Ground
R+ (RB)
Receive Positive
Data Line
Serial data received by the XTend Module Assembly
T+ (TB)
Transmit Positive
Data Line
Serial data sent from the XTend Module Assembly
PWR
Power
Optional power input that is connected internally
to the front power connector
1, 4, 6
© 2012 Digi Internatonal, Inc.
not used
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XTend™ RF Module - Product Manual
Wiring Diagrams
Figure B-23. XTend Module Assembly in an RS-485 (4-wire) environment
Figure B-24. XTend Module Assembly in an RS-422 environment
RS-485/422 Connection Guidelines
The RS-485/422 protocol provides a solution for wired communications that can tolerate high
noise and push signals over long cable lengths. RS-485/422 signals can communicate as far as
4000 feet (1200 m). RS-232 signals are suitable for cable distances up to 100 feet (30.5 m).
RS-485 offers multi-drop capability in which up to 32 nodes can be connected. The RS-422
protocol is used for point-to-point communications.
Suggestions for integrating the XTend RF Module with the RS-485/422 protocol:
© 2012 Digi Internatonal, Inc.
1.
When using Ethernet twisted pair cabling: Select wires so that T+ and T- are connected to
each wire in a twisted pair. Likewise, select wires so that R+ and R- are connected to a
twisted pair. (For example, tie the green and white/green wires to T+ and T-.)
2.
For straight-through Ethernet cable (not cross-over cable) - The following wiring pattern
works well: Pin3 to T+, Pin4 to R+, Pin5 to R-, Pin6 to T-
3.
Note that the connecting cable only requires 4 wires (even though there are 8 wires).
4.
When using phone cabling (RJ-11) - Pin2 in the cable maps to Pin3 on opposite end of
cable and Pin1 maps to Pin4 respectively.
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XTend™ RF Module - Product Manual
X-CTU Software
X-CTU is a Digi-provided software program used to interface with and configure Digi RF Modules.
The software application is organized into the following four tabs:
• PC Settings tab - Setup PC serial ports for interfacing with an RF module
• Range Test tab - Test the RF module's range and monitor packets sent and received
• Terminal tab - Set and read RF module parameters using AT Commands
• Modem Configuration tab - Set and read RF module parameters
Figure B-11. X-CTU User Interface (PC Settings, Range Test, Terminal and Modem Configuration tabs)
NOTE: PC Setting values are visible at the bottom of the Range Test, Terminal and Modem Configuration tabs. A shortcut for editing PC Setting values is available by clicking on any of the values.
Installation
Double-click the "setup_X-CTU.exe" file and follow prompts of the installation screens. This file is
located in the 'software' folder of the Digi CD and also under the 'Downloads' section of the
following web page: www.digi.com/support.
Setup
To use the X-CTU software, a module assembly (An RF module mounted to an interface Board)
must be connected to a serial port of a PC.
NOTE: Failure to enter AT Command Mode is most commonly due to baud rate mismatch. The
interface data rate and parity settings of the serial port ("PC Settings" tab) must match those of
the module (BD (Baud Rate) and NB (Parity) parameters respectively).
Serial Communications Software
A terminal program is built into the X-CTU Software. Other terminal programs such as
"HyperTerminal" can also be used to configure modules and monitor communications. When
issuing AT Commands through a terminal program interface, use the following syntax:
Figure B-12. Syntax for sending AT Commands
NOTE: To read a parameter value stored in a register, leave the parameter field blank.
The example above issues the DT (Destination Address) command to change destination address
of the module to "0x1F". To save the new value to the module’s non-volatile memory, issue WR
(Write) command after modifying parameters.
© 2012 Digi Internatonal, Inc.
72
Appendix C: Additional Information
1-Year Warranty
WARRANTY PERIOD: Digi warranties hardware Product for a period of one (1) year.
WARRANTY PROCEDURE: Upon return of the hardware Product Digi will, at its option, repair or
replace Product at no additional charge, freight prepaid, except as set forth below. Repair parts
and replacement Product will be furnished on an exchange basis and will be either reconditioned or
new. All replaced Product and parts become the property of Digi. If Digi determines that the
Product is not under warranty, it will, at the Customers option, repair the Product using current
Digi standard rates for parts and labor, and return the Product FedEx Ground at no charge in or out
of warranty.
© 2012 Digi International Inc.
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XTend™ RF Module - Product Manual
Contact Digi
For the best in wireless data solutions and support, please use the following resources:
Documentation:
www.digi.com/support
Technical Support:
Phone.
(866) 765-9885 toll-free U.S.A. & Canada
(801) 765-9885 Worldwide
Live Chat.
www.digi.com
E-support:
http://www.digi.com/support/eservice/eservicelogin.jsp
Office hours are 8:00 am - 5:00 pm [U.S. Mountain Standard Time]
© 2012 Digi Internatonal, Inc.
74

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