Insys GSM Small 11-02-01-03-02.001 Manuale Utente

7. Command Overview 

 

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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): 

Meaning 

0

Final

Command executed, no error

1

Final

Connection established if parameter setting X=0

 

Final

Connection established if parameter setting X>0 <text>: E.g. 
‘CONNECT 9600/RLP’. The data transmission rate is then 9.600 
bit/s.

2

Non-
synchronized

Ring tone recognized

3

Final

Connection not established or disconnected

4

Final

Invalid command or command line too long

5

Final

No dial tone, connection setup not successful, wrong operating 
mode

6

Final

Remote terminal busy

7

Final

Timeout for connection setup

 

Version  1.00 / 09.04