Api Frames; At Command; At Command - Queue Parameter Value - Digi XBee ZigBee S2D User Manual

API frames

The following sections illustrate the types of frames encountered while using the API.

AT command

Frame Type: 0x08
Used to query or set module parameters on the local device. This API command applies changes after executing
the command. (Changes made to module parameters take effect once changes are applied.) The API example
below illustrates an API frame when modifying the NJ parameter value of the module
Frame Fields
Start Delimiter
Length
Frame-specific Frame Type
Data
Frame ID
AT Command
Parameter
Value
(optional)
Checksum
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.
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
Start Delimiter
Length
XBee/XBee-PRO ZigBee RF Modules User Guide
Offset Example Description
0 0x7E
MSB 1 0x00 Number of bytes between the length and the checksum
LSB 2 0x04
3 0x08
4 0x52 (R) Identifies the serial port data frame for the host to correlate with a
subsequent ACK (acknowledgment). If set to 0, no response is sent.
5 0x4E (N) Command Name - Two ASCII characters that identify the AT
Command.
6 0x4A (J)
If present, indicates the requested parameter value to set the given
register.
If no characters present, register is queried.
7 0x0D 0xFF - the 8 bit sum of bytes from offset 3 to this byte.
Offset Example Description
0 0x7E
MSB 1 0x00 Number of bytes between the length and the checksum
LSB 2 0x05
API frames
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