At command summary, Answer command, Descriptions – Multi-Tech Systems MT5634MSV User Manual
Page 39: Attention code, Bell 212a mode, Carrier control command, Communication standard command, Dial command, Dial string modifiers, Enter key

4 AT Commands, S-Registers, and Result Codes
31
AT Command Summary
Command:
AT
Attention Code
Values:
n/a
Description:
The attention code precedes all command lines except A/, A:,
and the escape sequence.
Command:
ENTER Key
Values:
n/a
Description:
Press the E
NTER
or R
ETURN
key to execute most commands.
Command:
A
Answer
Values:
n/a
Description:
Answer an incoming call before the final ring.
Command:
A/
Repeat Last Command
Values:
n/a
Description:
Repeat the last command string. Do not precede this command
with AT. Do not press E
NTER
to execute.
Command:
B
n
Communication Standard Setting
Values:
n = 0–3, 15, 16
Default:
1 and 16
Description:
B0
Select ITU-T V.22 mode when modem is at 1200 bps.
B1
Select Bell 212A when modem is at 1200 bps.
B2
Deselect V.23 reverse channel (same as B3).
B3
Deselect V.23 reverse channel (same as B2).
B15
Select V.21 when the modem is at 300 bps.
B16
Select Bell 103J when the modem is at 300 bps.
Command:
C
n
Carrier Control
Values:
n = 1
Default:
1
Description:
C0
Transmit carrier always off. (Not supported.)
C1
Normal transmit carrier switching (included for backward
compatibility with some software).
Command:
D
s
Dial
Values:
s = dial string (phone number and dial modifiers)
Default:
none
Description:
Dial telephone number s, where s may up to 40 characters long
and include the 0–9, *, #, A, B, C, and D characters, and the L,
P
, T, V, W, S, comma (,), semicolon (;), !, @, ^ and $ dial string
modifiers.
Dial string modifiers:
L
Redial last number. (Must be placed immediately after
ATD
.)
P
Pulse-dial following numbers in command.
T
Tone-dial following numbers in command (default).