Call Control
3-12 AT Commands Reference Manual June 30, 20 08

Switching From Data Mode to Command Mode

To switch the connection from Data mode to Command mode, send the Escape Sequence
command (+++).
If the modem responds with "OK" to the Escape command, the modem is in Command mode and
the dial connection is still active, and you can use the AT command set.
Note: The character '+' in the Escape Sequence pattern can be changed using the S2 S-register.
Refer to “S, Bit Map Registers”, page 3-284.
Escape is detected only by the G24 and not by the remote side. The remote side stays in
the Data mode.

Hanging Up

If you are using a communications program, use the "Hang up" or "Disconnect" AT command in
the program to disconnect the call.
When using computers in the "Dumb Terminal mode", return to the Command mode by typing
the Escape Sequence, +++, and then hang up by typing the Hang up command as follows:
ATH <Enter>
If the G24 responds with "OK", the dial connection is closed.

Dialing to an Electronic Telephone Service

When you dial to an electronic telephone service such as telephone banking, you must typically
instruct the modem to dial a number, then to wait for call establishment, and then send the
password for entering the banking account. A typical command line might look like this:
ATD876-5555,123456; <Enter>
The modem dials the number, then pauses to wait for the call connection (the comma in the
command line causes the pause).
You can also create a longer pause by including several commas in a row in the command line,
and then send the password to the service.
Receiving a Data Call
ATA <Enter>
This command instructs the modem to be the "answering modem". Either party may be the
answering or the originating modem, but both parties cannot be the same modem at the same
time.
You hear the modem handshake and see the result code "CONNECT".
Note: Outgoing Voice Call during CSD Call, when switching to Command mode.
If using Dial Command to make Outgoing Voice Call, currently active CSD Call is
dropped and the new Voice Call is generated.