Digi International Inc XBEEPRO2 Manual Do Utilizador

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XBee®/XBee‐PRO® ZB RF Modules 
© 2011 Digi International, Inc.
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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.)
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.
Frame Fields
Offset Example
Description
A
P
I
 
P
a
c
k
e
t
Start Delimiter
0 0x7E
Length
MSB 1 0x00
Number of bytes between the length and the checksum
LSB 2 0x04
Frame-specific Data  Frame Type
3 0x08
Frame ID
4 0x52 (R)
Identifies the UART data frame for the host to correlate 
with a subsequent ACK (acknowledgement). If set to 0, 
no response is sent.
AT Command
5 0x4E  (N)
Command Name - Two ASCII characters that identify the 
AT Command.
6 0x4A  (J)
Parameter Value
(optional)
If present, indicates the requested parameter
value to set the given register.
If no characters present, register is queried.
Checksum
7  0x0D
0xFF - the 8 bit sum of bytes from offset 3 to this byte.
Frame Fields
Offset Example
Description
A
P
I
 
P
a
c
k
e
t
Start Delimiter
0 0x7E
Length
MSB 1 0x00
Number of bytes between the length and the checksum
LSB 2 0x05
Frame-specific Data  Frame Type
3 0x09
Frame ID
4 0x01
Identifies the UART data frame for the host to correlate 
with a subsequent ACK (acknowledgement). If set to 0, 
no response is sent.
AT Command
5 0x42 (B)
Command Name - Two ASCII characters that identify the 
AT Command.
6 0x44 (D)
Parameter Value
(ATBD7 = 115200 
baud)
7 0x07
If present, indicates the requested parameter
value to set the given register.
If no characters present, register is queried.
Checksum
8 0x68
0xFF - the 8 bit sum of bytes from offset 3 to this byte.