Chapter 6 – Fax Class 1 and Class 1.0 Commands
Multi-Tech Systems, Inc. SocketModem MT5600SMI Developer’s Guide 94
Service Class 1 Commands

Command: +FAR Adaptive Reception Control

Description: If Adaptive Reception is enabled, the modem adaptively detects the s elected
message carrier or V.21 control messages. If the expected carrier is det ected,
the modem operates as specified in the respective +FRM=<mod or
+FRH=<mod commands. If V.21 flag preamble is detected instead, the
modem issues a +FRH:3 intermediate result code, and then executes an
implied +FRH=3 command.
Defined Values: <value> Decimal number corresponding to the selected option.
0 Disable Adaptive Reception. (Default.)
1 Enable Adaptive Reception.
Reporting Current or Selected Values:
Command: +FAR?
Response: +FAR: <value
Example: +FAR: 0 For the default setting.
Reporting Supported Range of Parameter Values:
Command: +FAR=?
Response: +FAR: (<value> range )
Example: +FAR: (0,1)

Command: +FCL Carrier Loss Timeout

Description: This parameter allows the DTE to select the modem’s loss-of-c arrier delay
between initial loss-of-carrier and qualified loss-of-carrier , when the modem
will give up and exit a receive mode. Intermediate (less than FCL tim eout)
loss-of-carrier should be indicated by insertion of the SQ-BAD sign al quality
indicator in the received data stream.
In unframed receive modes, if the modem detects RTC as described in
Recommendation T.30 prior to initial loss of the high speed carrier, or if the
modem detects V.21 carrier after initial loss of high speed carrier, t hen the
modem immediately accepts the loss-of-carrier as qualified, witho ut waiting for
the FCL timer to expire.
In HDLC receive modes, if the modem detects HDLC abort prior to initial loss
of the high speed carrier, or if the modem detects V.21 carrier after initial loss
of high speed carrier, then the modem l immediately accepts the loss -of-
carrier as qualified, without waiting for the FCL timer to expire.
Defined Values: <value> Decimal number representing the loss-of-carrier delay tim e in units of
100 ms. The range is 0 - 255.
Reporting Current or Selected Values:
Command: +FCL?
Response: +FCL: <time
Example: +FCS: 0 For the default setting.
Reporting Supported Range of Parameter Values:
Command: +FCL=?
Response: +FCL: (time range)
Example: +FCL: (0-255)