Helmholz 700-751-HSM11, Руководство пользователя, Страница: 57 / 99

Helmholz Modem 56k 4.1 57
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 con-
nection 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
HELMHOLZ Modem 56k will, for example, always attempt to establish a 56000
baud connection, even if the serial interface is only set to 9600 baud. Without er-
ror 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