Chapter 4 – Advantech PCM-3601 User Manual
Page 21
Page: 19
Chapter 4
AT Commands
This chapter describes the basic modem commands in alphabetical order.
Some commands have factory default settings, for which you can refer to
your Getting Started manual Command Summary table.
4.1 Prefix, Repeat and Escape Commands
AT Attention. Precede all command lines except A/ and +++
A/ Re-execute the last command in command buffer
+++ Escape characters, requires guard time before and after
4.2 Dial Commands and Dial Modifiers
D
Originate a call
S=n Dial the n
th
stored number
T
Touch tone dialing
P
Pulse dialing
R
Dial in answer mode
W Wait for second dial tone
L
Re-Dial the last valid
telephone number
,
Pause
!
Flash
;
Return to command state
4.3 Operation
Commands
A
Answer incoming call
B0
CCITT or ITU-T compatibility
B1
Bell protocol only
E0
Disable command echo
E1
Enable echo command
characters
H0
Hang up the connection (on-
hook)
H1
Go off-hook to make a call
I0
Reports product code
I1
Calculates the ROM
checksum
I3
Reports firmware version
L0
Low volume
L1
Low volume
L2 Medium
volume
L3
High volume
M0
Speaker off at all times
M1
Speaker on until CD
detected
M2
Speaker always on
N0
Fixed data rate follow *N
command
N1
Enable adaptive data rate
O0
Return to data-link without
retrain
O1
Return to data-link with
retrain
Q0
Modem sends response
codes
Q1
Do not send response codes
Sr? Display the value in register
Sr=n Set register r to a value n
V0
Display response codes in
digit form
V1
Display response codes in
words
W0 Disable V.42 response codes,