Digi 90031300 User Manual

Page of 160
Appendix F
105
AT& (Ampersand) Commands
&B
n
Autoretrain
Defines modem action when it receives a poor signal.
&B0
:
Hang up on a poor received signal.
*
&B1
:
Retrain on a poor received signal.  Hang up if condition persists longer than the threshold set
in register 
S7
.
&B2
:
Do not hang up; do not retrain (tolerate any connection).
Result Codes:
OK
Returned when 
= 0, 1 or 2.
ERROR
Returned for any other value of 
n
.
&C
n
Data Carrier Detect Option (Async Only)
Controls how the state of the DCD or RLSD (Receive Line Signal Detect) relates to the carrier from the
remote system.  Always use 
&C1
 for Sync mode.
&C0
:
State of carrier from remote modem is ignored.  RLSD circuit is always on.
*
&C1
:
State of carrier from remote modem is tracked.  RLSD circuit reflects the state of the carrier.
Result Codes:
OK
Returned when 
= 0 or 1.
ERROR
Returned for any other value of 
n
.
&D
n
Data Terminal Ready Option
Defines modem action when it receives a poor signal.
&D0
:
DTR ignored.
&D1
:
Go to command mode when DTR changes from on to off.
*
&D2
:
Hang up and go to command mode when DTR changes from on to off.  Auto answer is
disabled if DTR is low.
&D3
:
Reset when DTR changes from on to off.
Result Codes:
OK
Returned when 
= 0, 1, 2 or 3.
ERROR
Returned for any other value of 
n
.
&F
Load Factory Settings
Loads the configuration programmed at the factory.  This command replaces all command options and S
register settings in the active configuration with the factory values stored in the nonvolatile RAM.
&F
:
Recall factory setting as active configuration.