XBee®/XBee‐PRO® ZB SMT RF Modules
Frame Fields
Offset Example
0 0x7E
Description
Start Delimiter
Length
MSB 1 0x00
LSB 2 0x04
3 0x08
Number of bytes between the length and the checksum
A
P
I
Frame-specific Data Frame Type
Frame ID
Identifies the serial port data frame for the host to
correlate with a subsequent ACK (acknowledgement). If
set to 0, no response is sent.
4 0x52 (R)
P
a
c
k
e
t
AT Command
5 0x4E (N)
6 0x4A (J)
Command Name - Two ASCII characters that identify the
AT Command.
If present, indicates the requested parameter
value to set the given register.
If no characters present, register is queried.
Parameter Value
(optional)
Checksum
7
0x0D
0xFF - the 8 bit sum of bytes from offset 3 to this byte.
The above example illustrates an AT command when querying an NJ value.
AT Command - Queue Parameter Value
Frame Type: 0x09
This API type allows module parameters to be queried or set. In contrast to the “AT Command” API type, new
parameter values are queued and not applied until either the “AT Command” (0x08) API type or the AC (Apply
Changes) command is issued. Register queries (reading parameter values) are returned immediately.
Example: Send a command to change the baud rate (BD) to 115200 baud, but don't apply
changes yet. (Module will continue to operate at the previous baud rate until changes are applied.)
Frame Fields
Offset Example
0 0x7E
Description
Start Delimiter
Length
MSB 1 0x00
LSB 2 0x05
3 0x09
Number of bytes between the length and the checksum
A
P
I
Frame-specific Data Frame Type
Frame ID
Identifies the serial port data frame for the host to
correlate with a subsequent ACK (acknowledgement). If
set to 0, no response is sent.
4 0x01
P
a
c
k
e
t
5 0x42 (B)
6 0x44 (D)
Command Name - Two ASCII characters that identify the
AT Command.
AT Command
If present, indicates the requested parameter
value to set the given register.
If no characters present, register is queried.
Parameter Value
(ATBD7 = 115200
baud)
7 0x07
8 0x68
Checksum
0xFF - the 8 bit sum of bytes from offset 3 to this byte.
Note: In this example, the parameter could have been sent as a zero-padded 2-byte or 4-byte value.
ZigBee Transmit Request
Frame Type: 0x10
A Transmit Request API frame causes the module to send data as an RF packet to the specified destination.
The 64-bit destination address should be set to 0x000000000000FFFF for a broadcast transmission (to all
devices). The coordinator can be addressed by either setting the 64-bit address to all 0x00s and the 16-bit
address to 0xFFFE, OR by setting the 64-bit address to the coordinator's 64-bit address and the 16-bit address
to 0x0000. For all other transmissions, setting the 16-bit address to the correct 16-bit address can help improve
performance when transmitting to multiple destinations. If a 16-bit address is not known, this field should be
set to 0xFFFE (unknown). The Transmit Status frame (0x8B) will indicate the discovered 16-bit address, if
successful.
© 2010 Digi International, Inc.
101
DCD [ DIGITAL CORE DESIGN ]
