AT Commands Protocol

General System Abbreviations

The basic system configuration contains a modem and a terminal.

The G24-L is the modem and may be referred to as the DCE, the phone, the mobile or the radio.

The terminal may be referred to as the DTE or the TE.

AT Commands Protocol

The figure below shows a general messaging sequence of AT commands protocol between the terminal and the G24-L.

Terminal

G24-L

 

Command

 

 

 

 

 

 

Response

 

N

 

Results Code

 

 

 

Indications

 

M

 

 

 

 

N, .,0,1 =K

M, .,0,1 =L

Figure 2-1: AT Commands Protocol

The AT commands interface is basically a Modem Services Upon Request.

Communication (almost) always begins from the terminal side. This means that any service should be requested from the terminal. Thus a request is called a "command".

Each command must be answered by a "results code" from the G24-L. The results code reports the command status to the terminal.

Some commands may include several "Response" requests (between 0 to K) to send data back to the terminal.

Some commands may initiate a mode in which, when specified events are generated in the G24-L, "Indicator" messages are sent asynchronously. Indicators can be between 0 to L.

The G24-L can echo characters received from the terminal (commands) back to the terminal.

2-2

G24-L AT Commands Reference Manual

April 15, 2008

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PIONEERPOS G24-LC manual AT Commands Protocol, General System Abbreviations