13
AT commands
All commands sent to the modem must begin with the attention code
AT (except for the +++ (escape) and the A/ (repeat)) commands. The
following tables group the commands by function.
Table 3
Prefix, repeat, and escape commands
Command
Description
AT
A/
+++
Command line prefix that tells the modem a command
follows; must precede all of the commands, except for the
+++ (escape) and A/ (repeat) commands.
Re-execute last command line, don't precede this command
with AT or press <Enter? at the end of the command line.
Escape code: go from on-line mode to command mode;
One second pause before and after escape code entry. The
c++ is not followed by a carriage return.
Table 4
Set 300/1200 BPS protocol
Command
Description
B0
B1
Uses CCITT V.22/2100 Hz answer backtone at 1200 BPS
Uses Bell 212A/2225 Hz answer backtone operation at
1200 BPS
Table 5
Dialing options
Command
Description
D
P
R
T
!
@
W
,
;
Dial telephone number
Pulse dialing
Originate call in answer mode
Touch–tone dial
0.5 second hookflash
Wait for silence (default 5 seconds)
Wait for dial tone (default 30 seconds; see register S7)
Pause (default 2 seconds; see register S8)
Return to command mode after dialing
