Rockwell RCV144ACx, Command Reference Manual

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AT Command Reference Manual
3-2 1048
3.2 AT COMMAND SET
The modem will respond to the commands detailed below. Parameters applicable to each command are listed with the
command description. The defaults shown for each configuration command are those used in the Rockwell factory profile 0.
3.2.1 AT Commands
A/ - Re-execute Command
The modem behaves as though the last command line had been re-sent by the DTE. "A/" will repeat all the commands in the
command buffer.
The principal application of this command is to place another call (using the Dial command) that failed to connect due to a
busy line, no answer, or a wrong number. This command must appear alone on a command line. This command should not
be terminated by a carriage return.
AT= x - Write to Selected S-Register
This command writes the value x to the currently selected S-Register. An S-Register can be selected by using the ATSn
command. All of the S-Registers will return the OK response if x is a number. Some registers may not be written due to
country specific PTT limitations.
Result Codes
OK For all arguments.
AT? - Read Selected S-Register
This command reads and displays the selected S-Register. An S-Register can be selected by using the ATSn command.
Result Codes:
OK For all arguments.
A - Answer
The modem will go off-hook and attempt to answer an incoming call if correct conditions are met. Upon successful
completion of answer handshake, the modem will go on-line in answer mode. This command may be affected by the state of
Line Current Sense, if enabled. (Most countries do not require Line Current Sense.) Operation is also dependent upon
+FCLASS command and country-specific requirements.
If +FCLASS=0 is selected, the modem will enter the connect state after exchanging carrier with the remote modem. If no
carrier is detected within a period specified in register S7, the modem hangs up. Any character entered during the connect
sequence will abort the connection attempt.
If +FCLASS=1 or 2 is selected, the modem will go off-hook in V.21 answer mode. It will generate the V.21 2100 Hz answer
tone for 3 ± 0.5 seconds and, following a delay of 70 ms, will proceed as if the +FTH=3 command were issued. At any stage
up to (but excluding) the +FTH=3 command state, any character will abort the communication. (See the description of the
+FTH command for details.)
Bn - CCITT or Bell
When the modem is configured to allow either option, the modem will select Bell or CCITT modulation for a line speed
connection of 300 or 1200 bps according to the parameter supplied. Any other line speed will use a CCITT modulation
standard. The parameter value, if valid, is written to S27 bit 6. (Also, see ATFn command.)
B0 Selects CCITT operation at 300 or 1200 bps during Call Establishment and a subsequent
connection. (Default for W-class models.)
B1 Selects BELL operation at 300 or 1200 bps during Call Establishment and a subsequent
connection. (Default for US models.)
Result Codes:
OK n = 0 or 1.
ERROR Otherwise.