Digi XBee3 802.15.4 User Manual
XBee3® 802.15.4
Radio Frequency (RF) Module
User Guide
Revision history—90002273
Revision Date Description
A February 2018 Initial release.
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© 2018 Digi International Inc. All rights reserved.
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XBee3® 802.15.4 RF Module User Guide
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Contents
XBee3® 802.15.4 RF Module User Guide
Applicable firmware and hardware 8
Change the firmware protocol 8
Getting started
Verify kit contents 10
Assemble the hardware 10
Plug in the XBee3 802.15.4 RF Module 11
How to unplug an XBee module 12
Configure the device using XCTU 12
Configure remote devices 12
Configure the devices for a range test 13
Perform a range test 14
Modes
Serial modes 18
Transparent operating mode 18
API operating mode 18
Command mode 18
Enter Command mode 19
Send AT commands 19
Apply command changes 20
Exit Command mode 20
Operation
Software libraries 22
Addressing 22
Send packets to a specific device 22
Addressing modes 22
Maximum payload 23
Maximum payload rules 23
Working with Legacy devices 23
Networking 24
MAC Mode configuration 24
XBee retries configuration 25
Transmit status based on MAC mode and XBee retries configurations 25
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Peer-to-peer networks 26
Clear Channel Assessment (CCA) 26
CCA operations 27
Serial interface 27
Serial receive buffer 27
Serial transmit buffer 27
UART data flow 28
Flow control 28
Sleep support 30
Sleep modes 30
Sleep parameters 30
Sleep current 30
Sleep pins 31
Node discovery 31
Remote configuration commands 31
Send a remote command 31
Apply changes on remote devices 32
Remote command responses 32
AT commands
Network commands 34
ID (Extended PAN ID) 34
C8 (802.15.4 Compatibility) 34
NI (Node Identifier) 36
NT (Node Discover Timeout) 36
ND (Network Discover) 36
NO (Node Discovery Options) 37
NP (Maximum Packet Payload Bytes) 37
Addressing commands 38
SH (Serial Number High) 38
SL (Serial Number Low) 38
MY (16-bit Source Address) 38
DH (Destination Address High) 38
DL (Destination Address Low) 39
RR (XBee Retries) 39
TO (Transmit Options) 39
MM (MAC Mode) 40
DD (Device Type Identifier) 40
RF interfacing commands 41
PL (TX Power Level) 41
PP (Output Power in dBm) 41
CH (Operating Channel) 41
CA (CCA Threshold) 42
RN (Random Delay Slots) 42
DB (Last Packet RSSI) 42
UART serial interfacing 43
BD (Interface Data Rate) 43
NB (Parity) 44
SB (Stop Bits) 44
AP(API Enable) 45
RO (Packetization Timeout) 45
FT command 45
D6 (DIO6/RTS) 46
D7 (DIO7/CTS) 46
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Command mode options 46
CN (Exit Command mode) 47
CT (Command Mode Timeout) 47
GT (Guard Times) 47
CC (Command Character) 47
Sleep settings 47
SM (Sleep Mode) 48
D8 (DIO8/DTR/SLP_RQ) 48
D9 (DIO9/ON_SLEEP) 48
I/O settings commands 49
D0 (DIO0 Configuration) 49
D1 (DIO1 Configuration) 49
D2 (DIO2 Configuration) 50
D3 (DIO3 Configuration) 50
D4 (DIO4 Configuration) 51
D5 (DIO5/Associate Configuration) 51
P0 (DIO10/PWM0 Configuration 52
P1 (DIO11 Configuration) 52
P5 (DIO15 Configuration) 53
PR (Pull-up/Down Resistor Enable) 53
PD (Pull Up/Down Direction) 54
LT command 54
Diagnostic commands 55
AI (Association Indication) 55
EA (ACK Failures) 55
EC (CCA Failures) 55
VR (Firmware Version) 56
VL (Version Long) 56
VH command 56
HV (Hardware Version) 56
%V command 56
TP command 57
CK (Configuration CRC) 57
FR (Software Reset) 57
Memory access commands 57
AC (Apply Changes) 57
WR (Write) 58
RE (Restore Defaults) 58
Operate in API mode
API mode overview 60
API frame specifications 60
API operation (AP parameter = 1) 60
API operation-with escaped characters (AP parameter = 2) 60
API frame format 61
Calculate and verify checksums 62
Frame descriptions 64
API frames 64
TX Request: 64-bit address frame - 0x00 64
TX Request: 16-bit address - 0x01 66
AT Command Frame - 0x08 67
AT Command - Queue Parameter Value frame - 0x09 69
Remote AT Command Request frame - 0x17 70
RX Packet: 64-bit Address frame - 0x80 71
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Receive Packet: 16-bit address frame - 0x81 72
AT Command Response frame - 0x88 73
TX Status frame - 0x89 75
Modem Status frame - 0x8A 77
Remote Command Response frame - 0x97 78
XBee3® 802.15.4 RF Module User Guide
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XBee3® 802.15.4 RF Module User Guide
XBee3 802.15.4 RF Modules are embedded solutions providing wireless end-point connectivity to
devices. These devices use the IEEE 802.15.4 networking protocol for fast point-to-multipoint or peerto-peer networking. They are designed for high-throughput applications requiring low latency and
predictable communication timing.
The XBee3 802.15.4 RF Module supports the needs of low-cost, low-power wireless sensor networks.
The devices require minimal power and provide reliable delivery of data between devices. The devices
operate within the ISM 2.4 GHz frequency band.
The XBee3 802.15.4 RF Module uses XBee3 hardware and the Silicon Labs EFR32 chipset. As the name
suggests, the 802.15.4 module is over-the-air compatible with our Legacy 802.15.4 modules (S1 and
S2C hardware).
For information about XBee3 hardware, see the XBee3 RF Module Hardware Reference Manual.
Applicable firmware and hardware 8
Change the firmware protocol 8
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XBee3® 802.15.4 RF Module User Guide Applicable firmware and hardware
Applicable firmware and hardware
This manual supports the following firmware:
n 802.15.4 version 20xx
It supports the following hardware:
n XBee3
Change the firmware protocol
You can switch the firmware loaded onto the XBee3 hardware to run either of the following protocols:
n Zigbee
n 802.15.4
To change protocols, use the Update firmware feature in XCTU and select the firmware. See the
XCTU User Guide.
XBee3® 802.15.4 RF Module User Guide
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Getting started
This section covers the following tasks and features:
Verify kit contents 10
Assemble the hardware 10
Configure the device using XCTU 12
Configure remote devices 12
Configure the devices for a range test 13
Perform a range test 14
XBee3® 802.15.4 RF Module User Guide
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Getting started Verify kit contents
Verify kit contents
The XBee3 802.15.4 RF Module development kit contains the following components:
Part
XBee3 Zigbee SMT module (3)
XBee Grove development board (3)
Micro USB cable (3)
Antenna - 2.4 GHz, half-wave dipole, 2.1 dBi, U.FL female, articulating
(3)
XBee stickers
Assemble the hardware
This guide walks you through the steps required to assemble and disassemble the hardware
components of your kit.
n Plug in the XBee3 802.15.4 RF Module
n How to unplug an XBee module
The kit includes several XBee Grove Development Boards. For more information about this hardware,
XBee3® 802.15.4 RF Module User Guide
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Getting started Assemble the hardware
see the XBee Grove Development Board documentation.
Plug in the XBee3 802.15.4 RF Module
This kit includes two XBee Grove Development Boards. For more information about this hardware,
visit the XBee Grove Development Board documentation.
Follow these steps to connect the XBee devices to the boards included in the kit:
1. Plug one XBee3 802.15.4 RF Module module into the XBee Grove Development Board.
Make sure the board is NOT powered (either by the micro USB or a battery) when
you plug in the XBee module.
For XBee SMT modules, align all XBee pins with the spring header and carefully push the
module until it is hooked to the board.
2. Once the XBee module is plugged into the board (and not before), connect the board to your
computer using the micro USB cables provided.
3. Ensure the loopback jumper is in the UART position.
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Getting started Configure the device using XCTU
How to unplug an XBee module
To disconnect your XBee module from the XBee Grove Development Board:
1. Disconnect the micro USB cable (or the battery) from the board so it is not powered.
2. Remove the XBee module from the board socket, taking care not to bend any of the pins.
Make sure the board is not powered when you remove the XBee module.
Configure the device using XCTU
XBee Configuration and Test Utility (XCTU) is a multi-platform program that enables users to interact
with Digi radio frequency (RF) devices through a graphical interface. The application includes built-in
tools that make it easy to set up, configure, and test Digi RF devices.
For instructions on downloading and using XCTU, see the XCTU User Guide.
Configure remote devices
You can communicate with remote devices over the air through a corresponding local device.
Note Configure the local device in API mode because remote commands only work in API mode.
Configure remote devices in either API or Transparent mode.
These instructions show you how to configure the LT command parameter on a remote device.
1. Add two XBee devices to XCTU.
2. Configure the first device in APImode and name it XBEE_A.
3. Configure the second device in either API or Transparent mode, and name it XBEE_B.
4. Disconnect XBEE_B from your computer and remove it from XCTU.
5. Connect XBEE_B to a power supply (or laptop or portable battery).
The Radio Modules area should look something like this.
Select XBEE_A and click the Discover radio nodes in the same network button .
6.
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Getting started Configure the devices for a range test
7. Click Add selected devices in the Discovering remote devices dialog. The discovered remote
device appears below XBEE_A.
8. Select the remote device XBEE_B, and configure the following parameter:
LT: FF (hexadecimal representation for 2550 ms)
Click the Write radio settings button .
9.
The remote XBee device now has a different LED blink time.
10. To return to the default LED blink times, change the LT parameter back to 0 for XBEE_B.
Configure the devices for a range test
When you connect the development board to a PC for the first time, the PC automatically installs
drivers, which may take a few minutes to complete.
1. Add the two devices to XCTU.
2. Select the first module and click the Load default firmware settings button.
3. Configure the following parameters:
ID: 2018
NI: LOCAL_DEVICE
AP: API Mode Enabled [1]
4. Click the Write radio settings button.
5. Select the other module and click the Default firmware settings button.
6. Configure the following parameters:
ID: 2015
NI: REMOTE_DEVICE
AP: Transparent mode [0] (The remote node must be in transparent mode to loop back
packets)
XBee3® 802.15.4 RF Module User Guide
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Getting started Perform a range test
7. Click the Write radio settings button.
After you write the radio settings for each device, their names appear in the Radio Modules
area. The Port indicates that the LOCAL_DEVICE is in API mode.
8. Disconnect REMOTE_DEVICE from the computer, remove it from XCTU, and connect it to its
own power supply.
9. Leave LOCAL_DEVICE connected to the computer.
Perform a range test
1. Go to the XCTU display for radio 1.
Click to discover remote devices within the same network. The Discover remote devices
2.
dialog appears.
3. Click Add selected devices.
XBee3® 802.15.4 RF Module User Guide
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Getting started Perform a range test
Click and select Range test. The Radio Range Test dialog appears.
4.
5. In the Select the local radio device area, select radio 1. XCTU automatically selects the
Discovered device option, and the Start Range Test button is active.
XBee3® 802.15.4 RF Module User Guide
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Getting started Perform a range test
Click to begin the range test.
6.
If the test is running properly, the packets sent should match the packets received. You will
also see the received signal strength indicator (RSSI) update for each radio after each
reception.
7. Move Radio 1 around to see the resulting signal strength at different distances. You can also
test different data rates by reconfiguring the BR (data rate) parameter on both radios. When
the test is complete, click Stop Range Test.
XBee3® 802.15.4 RF Module User Guide
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Modes
Serial modes 18
Command mode 18
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Modes Serial modes
Serial modes
The firmware operates in several different modes. Two top-level modes establish how the device
communicates with other devices through its serial interface: Transparent operating mode and API
operating mode. Use the AP command to choose Serial mode. XBee3 802.15.4 RF Modules use
Transparent operation as the default serial mode.
The following subsections describe how the serial port sends and receives data.
Transparent operating mode
Devices operate in this mode by default. The device acts as a serial line replacement when it is in
Transparent operating mode. The device queues all UART data it receives through the DIN pin for RF
transmission. When a device receives RF data, it sends the data out through the DOUT pin. You can set
the configuration parameters using Command mode.
Serial-to-RF packetization
Data is buffered in the incoming serial buffer until one of the following causes the data to be
packetized and transmitted:
1. No serial characters are received for the amount of time determined by the RO (Packetization
Timeout) parameter. If RO = 0, packetization begins when a character is received.
2. The maximum number of characters that will fit in an RF packet is received. There are a
number of factors that determine payload size. You can query the NP (Maximum Packet
Payload Bytes) to determine the maximum payload size based on current configuration. For
more information, see Maximum payload.
3. The Command mode Sequence, GT + CC + GT, (including spaces) is received; this is any data in
the serial receive buffer received before the sequence is transmitted. For more information,
see Enter Command mode.
If the device cannot immediately transmit (for instance, if it is already receiving RF data), the serial
data is stored in the serial receive buffer. The data is packetized and sent at any RO timeout or when
NP bytes are received.
If the serial receive buffer becomes full, hardware flow control must be implemented in order to
prevent overflow (loss of data between the host and device).
API operating mode
Application programming interface (API) operating mode is an alternative to Transparent mode. It is
helpful in managing larger networks and is more appropriate for performing tasks such as collecting
data from multiple locations or controlling multiple devices remotely. API mode is a frame-based
protocol that allows you to direct data on a packet basis. It can be particularly useful in large
networks where you need control over the operation of the radio network or when you need to know
which node a data packet is from. The device communicates UART or SPI data in packets, also known
as API frames. This mode allows for structured communications with serial devices.
For more information, see API mode overview.
Command mode
Command mode is a state in which the firmware interprets incoming characters as commands. It
allows you to modify the device’s firmware using parameters you can set using AT commands. When
XBee3® 802.15.4 RF Module User Guide
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Modes Command mode
you want to read or set any parameter of the device when operating in Transparent mode, you have
to send an AT command. Every AT command starts with the letters AT followed by the two characters
that identify the command the device issues and then by some optional configuration values.
Command mode is available on the UART interface in both Transparent and API modes.
The availability of AT commands in API mode does not imply that Command mode is available in API
mode. Also, Command mode may be entered whether or not API mode is configured, providing the
UART is the serial interface.
Enter Command mode
To get a device to switch into this mode, you must issue the following sequence: GT + CC(+++) + GT.
When GT is set to the default value, if the device sees a full second of silence in the data stream (the
guard time) followed by the string +++ (without Enter or Return) and another full second of silence, it
knows to stop sending data through and start accepting commands locally.
Note Do not press Return or Enter after typing +++ because it will interrupt the guard time silence
and prevent you from entering Command mode.
When you send the Command mode sequence, the device sends OK out the UART pin. The device may
delay sending the OK if it has not transmitted all of the serial data it received.
When the device is in Command mode, it listens for user input and is able to receive AT commands on
the UART. If CT time (default is 10 seconds) passes without any user input, the device drops out of
Command mode and returns to Receive mode.
You can customize the command character, the guard times and the timeout in the device’s
configuration settings. For more information, see CC (Command Character), CT (Command Mode
Timeout) and GT (Guard Times).
Troubleshooting
Failure to enter Command mode is often due to baud rate mismatch. Ensure that the baud rate of the
connection matches the baud rate of the device. By default, the BD parameter = 3 (9600 baud).
Send AT commands
Once the device enters Command mode, use the syntax in the following figure to send AT commands.
Every AT command starts with the letters AT, which stands for "attention." The AT is followed by two
characters that indicate which command is being issued, then by some optional configuration values.
To read a parameter value stored in the device’s register, omit the parameter field.
The preceding example changes the device's destination address (Low) to 0x1F.
To store the new value to non-volatile (long term) memory, send the WR (Write) command. This allows
parameter values that you modify to persist in the device's registry after a reset. Otherwise, the
device restores parameters to the previous values after a reset.
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Modes Command mode
Multiple AT commands
You can send multiple AT commands at a time when they are separated by a comma in Command
mode; for example, ATSH,SL.
Parameter format
Refer to the list of AT commands for the format of individual AT command parameters. Numeric
parameters will always be represented in hexadecimal format. Some AT commands have ASCII string
parameter, which will be represented as ASCII characters in Command mode and bytes in API mode.
Valid formats for hexadecimal values include with or without a leading 0x for example FFFF or 0xFFFF.
Response to AT commands
When you send a command to the device, the device parses and runs the command. If the command
runs successfully, the device returns an OK message.
Apply command changes
Any changes you make to the configuration command registers using AT commands do not take effect
until you apply the changes. For example, if you send the BD command to change the baud rate, the
actual baud rate does not change until you apply the changes. To apply changes:
1. Send the AC (Apply Changes) command.
or:
2. Exit Command mode.
Exit Command mode
1. Send the CN (Exit Command mode) command followed by a carriage return.
or:
2. If the device does not receive any valid AT commands within the time specified by CT
(Command mode Timeout), it returns to Transparent or API mode. The default Command mode
Timeout is 10 seconds.
For an example of programming the device using AT commands and descriptions of each configurable
parameter, see AT commands.
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Operation
Software libraries 22
Addressing 22
Maximum payload 23
Networking 24
Clear Channel Assessment (CCA) 26
Serial interface 27
Sleep support 30
Node discovery 31
Remote configuration commands 31
XBee3® 802.15.4 RF Module User Guide
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Operation Software libraries
Software libraries
One way to communicate with the XBee3 802.15.4 RF Module is by using a software library. The
libraries available for use with the XBee3 802.15.4 RF Module include:
n XBee Java library
n XBee Python library
The XBee Java Library is a Java API. The package includes the XBee library, its source code and a
collection of samples that help you develop Java applications to communicate with your XBee devices.
The XBee Python Library is a Python API that dramatically reduces the time to market of XBee
projects developed in Python and facilitates the development of these types of applications, making it
an easy process.
Addressing
Every RF data packet sent over-the-air contains a Source Address and Destination Address field in its
header. The XBee3 802.15.4 RF Module conforms to the 802.15.4 specification and supports both short
16-bit addresses and long 64-bit addresses. A unique 64-bit IEEE source address is assigned at the
factory and can be read with the SL (Serial Number Low) and SH (Serial Number High) commands. You
must manually configure short addressing. A device uses its unique 64-bit address as its Source
Address if its MY (16-bit Source Address) value is 0xFFFF.
Send packets to a specific device
To send a packet to a specific device using 64-bit addressing:
n Set the Destination Address (DL + DH) of the sender to match the Source Address (SL + SH) of
the intended destination device.
To send a packet to a specific device using 16-bit addressing:
1. Set the DL parameter to equal the MY parameter of the intended destination device.
2. Set the DH parameter to 0.
Addressing modes
802.15.4 frames have a source address, a destination address, and a destination PAN ID in the overthe-air (OTA) frame. The source and destination addresses may be either long or short and the
destination address may be either a unicast or a broadcast. The destination PAN ID is short and it may
also be the broadcast PAN ID (ID is set to 0xFFFF).
In Transparent mode, the destination address is set by the DH and DL parameters, but, in API mode, it
is set by the TX Request:64-bit address (0x00) or TX Request: 16-bit Address (0x01) frames. In either
Transparent mode or API mode, the destination PAN ID is set with the ID parameter, and the source
address is set with the MY parameter.
Broadcasts and unicasts
Broadcasts are identified by the 16-bit short address of 0xFFFF. Any other destination address is
considered a unicast and is a candidate for acknowledgments, if enabled.
Broadcast PAN ID
The Broadcast PAN ID is also 0xFFFF. Its effect is to traverse all PANs in the vicinity of a local device.
XBee3® 802.15.4 RF Module User Guide
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Operation Maximum payload
Short and long addresses
A short address is 16 bits and a long address is 64 bits. The short address is set with the MY
parameter. If the short address is 0xFFFF, then the address of the device is long and it is the serial
number of the device as read by the SH and SL parameters.
Maximum payload
The absolute maximum payload size for an 802.15.4 packet is 116 bytes. Depending on module
configuration, the actual maximum payload size will be reduced.
If you attempt to send an API packet with a larger payload than specified, the device responds with a
Transmit Status frame (0x89) with the Status field set to 74 (Data payload too large). When operating
in transparent mode, if you attempt to send data larger than the maximum payload size, the data will
be packetized and sent as multiple over-the-air transmissions. For more information, see Serial-to-RF
packetization.
Maximum payload rules
1. If you enable transmit compatibility (C8) with the Legacy 802.15.4 module (S1 hardware):
n There is a fixed maximum payload of 100 bytes
n The rest of the rules do not apply. They apply only whenyou disable transmit
compatibility with the Legacy 802.15.4 module.
2. The maximum achievable payload is 116 bytes. This is achieved when:
n Not using encryption.
n Not using the application header (MM is set to 1 or 2).
n Using the short source address.
n Using the short destination address.
3. If you are usingthe application header, the maximum achievable payload is reduced by 2 bytes
if not using encryption.
4. If you are using the long source address,the maximum achievable payload is reduced by 6
bytes (size of long address (8) - size of short address (2) = 6).
5. If you are using the long destination address,the maximum achievable payload is reduced by 6
bytes (the difference between the 8 bytes required for a long address and the 2 bytes required
for a short address).
Note You can query the NP command to determine the maximum achievable payload size based on
current parameters.
Working with Legacy devices
The Legacy 802.15.4 module (S1 hardware) transmits packets one by one. It does not transmit a
packet until it receives all expected acknowledgments of the previous packet or the timeout expires.
The XBee/XBee-PRO S2C 802.15.4 and XBee3 802.15.4 RF Modules enhance transmission by
implementing a transmission queue that allows the device to transmit to several devices at the same
time. Broadcast transmissions are performed in parallel with the unicast transmissions.
XBee3® 802.15.4 RF Module User Guide
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Operation Networking
This enhancement in the XBee/XBee-PRO S2C 802.15.4 and XBee3 802.15.4 RF Modules can produce
problematic behaviorunder certain conditions if the receiver is a Legacy 802.15.4 module (S1
hardware).
The conditions are:
n The sender is a XBee3 802.15.4 RF Module, and the receiver is a Legacy 802.15.4 module.
n The sender has the Digi header enabled (MM = 0 or 3) and RR (XBee Retries) > 0.
n The sender sends broadcast and unicast messages at the same time to the Legacy 802.15.4
module without waiting for the transmission status of the previous packet.
The effect is:
n The receiver may display duplicate packets.
The solution is:
n Set bit 0 of the C8 (802.15.4 compatibility) parameter to 1 to enable TX compatibility mode in the
XBee3 802.15.4 RF Module. This eliminates the transmission queue to avoid sending to multiple
addresses simultaneously. It also limits the packet size to the levels of the Legacy 802.15.4
module.
For information on the specific differences between an XBee3 and Legacy 802.15.4 devices, refer to
the Digi XBee3 802.15.4 Migration Guide.
Networking
MAC Mode configuration
Medium Access Control (MAC) Mode configures two functions:
1. Enables or disables the use of a Digi header in the 802.15.4 RF packet.
When the Digi header is enabled (MM = 0 or 3), duplicate packet detection is enabled as well as
certain AT commands.
MAC Modes 1 and 2 do not include a Digi header, which disables many features of the device. All
data is strictly pass-through. These modes are intended to provide some compatibility with
third-party 802.15.4 devices.
2. Enables or disables MAC acknowledgment request for unicast packets.
When MACACK is enabled (MM = 0 or 2), transmitting devices send packets with an ACK
request soreceiving devices send an ACK back (acknowledgment of RF packet reception)to
the transmitter. If the transmitting device does not receive the ACK, it re-sends the packet
upto three times or until the ACK is received.
MAC Modes 1 and 3 disable MAC acknowledgment. Transmitting devices send packets without
an ACK request soreceiving devices do not send an ACK back to the transmitter.
Broadcast messages are always sent with the MACACK request disabled.
The followingtable summarizesthe functionality.
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