At Commands - Digi XBee-PRO 900HP DigiMesh Kit User Manual

XBee transparent mode
Guard time silence
One second before
Do not press Return or Enter after typing the +++ because it will interrupt the guard
time silence and prevent the module from entering Command mode.
Once the device is in Command mode, it listens for user input for a while. If 10 seconds go by without
any user input, the device automatically drops out of Command mode and returns to Transparent
mode.

AT commands

The purpose of command mode is to read or change the configuration of the local XBee device. Every
module has a number of settings, like channel or network ID, that define its behavior. These settings
are identified by two characters, for example, CH for channel, and ID for network ID.
When you want to read or set any setting of the XBee module, you must send it an AT command.
Every AT command starts with the letters "AT" followed by the two characters that identify the
command being issued and then by some optional configuration values.
For example, to read and set the network ID setting:
// Enter command mode
+++OK
// Read the ID setting
ATID <Enter>
0
// Change the ID setting
ATID 2015 <Enter>
OK
Basic AT commands
AT
n
This command checks the connection with the module. This is like asking "Are you there?" and
the device replying "Yes." When you send this command, the module simply replies OK. If you
don't see an OK in response, you have probably timed out of command mode. Type the +++ to
go back into it.
XBee-PRO 900HP DigiMesh Kit User Guide
Command sequence
+++
Command mode
Guard time silence
One second after
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