Ericsson T39 At Command Reference page 159

ATM
Description:
Set command:
Read command:
Test command:
Test command
response:
Parameter:
<value>:
Result code (ATV1)
OK
CONNECT
RING
NO CARRIER
ERROR
NO DIALTONE
BUSY
NO ANSWER
Monitor Speaker Control
Defines the activity of the speaker. This command is ignored by the infrared modem
and is included for compatibility reasons only.
ATM[=][<value>]
ATM? Displays the current <value> setting.
ATM=? Shows if the command is supported.
M: (list of supported <value>s)
<value>
0
1-3
Result code (ATV0) Description
0 Acknowledges execution of a
command
1 A connection has been established;
the DCE is moving from command
state to on-line data state
2 The DCE has detected an
incoming call from the network
3 The connection has been
terminated, or the attempt
establish a connection failed
4 Command not recognized,
command line maximum length
exceeded, parameter value invalid,
or other problem with processing
the command line
6 No dial tone detected
7 Engaged (busy) signal detected
8 "@" (Wait for Quiet Answer) dial
modifier was used, but remote
ringing followed by five seconds of
silence was not detected before
expiration of the connection timer
Description
Off during the entire call
Default setting
Different On-modes
AT Commands Modem Terminated 157