Digi XBee SX User Manual

AT commands MAC/PHY commands
XBee®/XBee-PRO SX RF Module User Guide
66
MAC/PHY commands
The following AT commands are MAC/PHY commands.
AF (Available Frequencies)
You can query this read-only command to return a bitfield of the frequencies that are available in the
device’s region of operation. This command returns a bitfield. Each bit corresponds to a physical
channel.
Channels for these data rates are spaced 250 kHz apart.
Parameter range
0x1F FFFF FFFF FFF0 0000 0000 0000 - 0x1F FFFF FFFF FFFF FFFF FFFF FFFF
Default
Region Bitfield Operating frequency range
United States/Canada 0x1F FFFF FFFF FFFF FFFF FFFF FFFF 902 to 928 MHz
Australia
0x01FF FFFF FFFF if BR is 0/1
915 to 928 MHz
0x00FF FFFF if BR is 2
915 to 928 MHz
New Zealand
0x1FF FFFF FFFF if BR is 0/1
917 to 928 MHz
0x7FF if BR is 2
917 to 928 MHz
Brazil
0x1F FFFF FFFF FFFF FFFF if BR is 0/1
902 to 907.5MHz
0x07 FFFF FFFF if BR is 2
915 to 928 MHz
CM (Channel Mask)
CM allows you to selectively enable or disable channels used for RF communication. This is useful to
avoid using frequencies that experience unacceptable levels of RF interference, or to operate two
networks of radios on separate frequencies.
When CM is queried, it returns the operating channel mask based on what value BR is set to. When BR
is set to 2, a fixed channel mask is used (see the defaults below). A user-defined CM value is only used
when BR is set to 0 or 1.
This command is a bitfield. Each bit in the bitfield corresponds to a frequency as defined in the AF
(Available Frequencies) command. When you set a bit in CM and the corresponding bit in AF is 1, then
the device can choose that channel as an active channel for communication.
Note For Australia and New Zealand, CM is read-only.
A minimum of MF channels must be made available for the device to communicate on. You can use the
MF command to query the minimum number of channels required for operation. If a CM setting would
result in less than MF active channels being enabled, then the device returns an error. If there are
more active channels enabled than required by MF, then the device uses the first MF frequencies;
higher active frequencies may be unused in favor of lower ones.
All devices in a network must use an identical set of active channels in order to communicate.
Separate networks that are in physical range of each other should either be configured to use

Digi XBee SX Specifications

General

Brand	Digi
Model	XBee SX
Category	Control Unit
Language	English