Command Mode; At Command Mode - Digi XTend User Manual

Cyclic scanning
Each RF transmission consists of an RF Initializer and payload. The RF initializer contains initialization information
and all receiving modules must wake during the wake-up initializer portion of data transmission in order to be
synchronized with the transmitting module and receive the data.
The cyclic interval time defined by the SM (Sleep Mode) command must be shorter than the interval time defined by
LH (Wake-up Initializer Timer) command.
Correct Configuration (LH > SM): The length of the wake-up initializer exceeds the time interval of Cyclic Sleep. The
receiver is guaranteed to detect the wake-up initializer and receive the accompanying payload data.

Command mode

To modify or read module parameters, the module must first enter into Command Mode (state in which incoming
characters are interpreted as commands). Two command types are supported:
•
AT Commands
•
Binary Commands
For modified parameter values to persist in the module registry, changes must be saved to non-volatile memory using
the WR (Write) command. Otherwise, parameters are restored to previously saved values when the module is
powered off and then on again.

AT Command mode

To Enter AT Command Mode:
1. Send the 3-character command sequence "+++" and observe guard times before and after the command
characters. [refer to 'Default AT Command Mode Sequence' below.] The 'Terminal' tab (or other serial
communications software) of the X-CTU Software can be used to enter the sequence.
[OR]
2. Assert (low) the CONFIG pin and turn the power going to the module off and back on (or pulse the SHDN pin).
3. [If the module is mounted to a Digi RS-232/485 Interface Board, the result can be achieved by pressing the
configuration switch down for 2 seconds.]
Default AT Command Mode Sequence (for transition to Command Mode):
•
No characters sent for one second [refer to the BT (Guard Time Before) Command]
•
Input three plus characters ("+++") within one second
[refer to the CC (Command Sequence Character) Command.]
•
No characters sent for one second [refer to the AT (Guard Time After) Command.]
XTend RF Module User Guide
Modes of operation
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