Datasheet

7. Command Overview 39
7 Command Overview
7.1 General Information Regarding the Command Sets
The AT commands can only be entered locally via the serial interface if the device is
either in offline state (no active data connection) or on online command mode
(interrupted data connection). This document lists the most important commands. The
complete AT command set of the GSM engine TC35i is available on request.
The modem guideline V.25ter is applicable with regard to the time sequence of interface
commands.
The AT standard is a line-oriented command language. Each command consists of three
elements: Prefix, body and end character.
The prefix always consists of the letters “AT”; the only exception is the command “A/”.
The main part consists of the command name and pertinent parameters, if applicable.
Parameters are always displayed in angular brackets <...>. If parameters are optional,
this is additionally indicated by square brackets [...].
The input is not context-sensitive.
All commands are finalized using the carriage return character set which is set with the
command ATS3 (Default = <CR> = 0x0D). The backspace character which is set with the
command ATS5 can be used to delete falsely entered characters.
(Default = <BS> = 0x08).
Each command is acknowledged with a response according to V.25ter (set with ATV):
Response Code Type Meaning
OK
0 Final Command executed, no error
CONNECT
1 Final Connection established if parameter setting X=0
CONNECT
[<text>]
Final Connection established if parameter setting X>0 <text>: E.g.
‘CONNECT 9600/RLP’. The data transmission rate is then 9.600
bit/s.
RING
2 Non-
synchronized
Ring tone recognized
NO CARRIER
3 Final Connection not established or disconnected
ERROR
4 Final Invalid command or command line too long
NO DIALTONE
5 Final No dial tone, connection setup not successful, wrong operating
mode
BUSY
6 Final Remote terminal busy
NO ANSWER
7 Final Timeout for connection setup
Version 1.00 / 09.04