Specifications

Chapter 2 – AT Commands Overview
10 Multi-Tech Systems, Inc. CDMA C1 AT Commands Reference Guide
Serial Interface Settings
A modem serial interface is set with the following default values (factory settings):
● 115,200bps
● 8 bits data
● 1 stop bit
● no parity
● RTS/CTS flow control.
Note: Some models may have a different value for the default baud rate.
The +IPR, +IFC and +ICF commands can be used to change these settings, if required. Changes made using these
commands become effective immediately following the transmission of the successful command result (OK).
Overview
Use AT commands to communicate with modem equipment. The modem provides an AT command interface
over the serial link between the modem and a host application. The AT command format is an ASCII string that
always starts with “AT” and ends with a defined set of characters. The format is defined in detail later in this
chapter.
AT command communication between the host application and the modem is blocking: the host application
must wait for the completion of one command before issuing the next command. The behavior of the modem is
undefined if a new command is issued before the previous command’s result code is returned.
While AT command communication is generally host-driven, unsolicited responses may also be sent to the host
application when a certain events occur. Host applications should be prepared to receive unsolicited responses
from the modem at any time except during AT command entry.
AT+CREG=0<CR> Unsolicited response cannot occur between the ‘A’ and <CR>
<CR><LF> Unsolicited response will not occur here unless otherwise documented
OK<CR><LF> Unsolicited response can occur here
Multi-Tech supports only the AT commands listed in this document. Other AT commands may be functional as a
result of the baseline code, but they will not be supported by Multi-Tech. The status of undocumented
commands should not be assumed. We recommend that only the listed AT commands be used in a host
application.
Note: The test command option associated with AT commands may also be present for a large percentage of
the AT commands.