AT
Command Set
INSYS Modem 336/56k 4.1 (UL)
Command
Description
ATL<n>
Speaker volume
This command regulates the speaker volume (see command
ATM
).
ATL1
Speaker volume low (default)
ATL2
Speaker volume medium
ATL3
Speaker
volume
high
AT%L
Display level of the received signal
The value that is reported from the modem equals the already amplified level within the
modem, not the phone line level.
Large
AT%L
responses imply a low signal level; small values imply a high signal level
(009 = -9db, 043 = -43db)
AT*L<n>
Determines the automatic speed limitation
The automatic speed limitation is used to automatically achieve the least possible error
rate for connections without error correction.
In the factory settings the speed limitation is always switched on (
AT*L0
).
If the limitation is switched off (
AT*L1
), the modem will always establish the connection
on the phone side with the maximum possible speed (or the speed defined with
AT+MS
),
irrespective of the data rate at the serial interface. This means that the INSYS Modem 336
will, for example, always attempt to establish a 33600 baud connection, even if the serial
interface is only set to 9600 baud. Without error correction the high speed will obviously
lead to higher bit error rates, which is usually disruptive.
The automatic speed limitation (
AT*L0
) will limit the speed on the phone side to the
speed of the serial interface.
It should only be switched off if very low baud rates are employed or if the speed of the
serial interface is changed during the connection.
ATM<n>
Speaker control
This command regulates when the speaker is active
(See command
ATL<n>
).
ATM0
Speaker
always
OFF
ATM1
Speaker ON during dialing and connection setup (default)
ATM2
Speaker
always
ON
ATM3
Speaker on during connection setup
58
July 06
