COMSPHERE 3800Plus Modems
F-2 November 1996 3980-A2-GB30-20
Call Request Commands
Call Request commands are issued from the DTE to
the modem and are responsible for initiating any dial
calls. Call Request commands include Call Request with
Number Provided (CRN) and Call Request with Stored
Memory Address Provided (CRS).
Call Request with Number Provided (CRN)
The
CRN command dials the telephone number
entered from the DTE. CRN is similar to the ATD
command.
The CRN command format is:
CRNn
Where: n is the dial string. The following
characters are permitted:
T DTMF Dialing
P
Pulse Dialing
0–9 DTMF T
ones or
Pulse Dialed Digits
* #
A B C D
DTMF Tones
R
Reverse Dial
: Wait for Dial Tone
, or < User-Defined Pause
&
Flash Hook
= or > Delimiters
Call Request with Stored Memory
Address Provided (CRS)
The
CRS command dials the telephone number stored
in the request directory location. CRS is similar to the
ATDS command.
The CRS command format is:
CRSx
Where: x is directory location 1–10.
The modem responds to the command with either a
VAL (valid) or INV (invalid) response followed by a call
progress report such as connect (CNX) or failure (CFI).
Call Response
Call Failure Indication (CFI)
The CFI response is issued to the DTE if the modem
fails a CRN or CRS command. CFI is similar to the A
T
result codes BUSY
, NO ANSWER, NO CARRIER, NO
DIALT
ONE, and ERROR.
The CFI response format is:
CFIxx
Where: xx is one of
ET Engaged tone
NS Number not stored
CB Local DCE busy
R
T
Timeout on ring tone
AB
Abort call on time-out
NT
Answer tone not detected
FC Forbidden call
ET is similar to the Call Failure Messages, Busy Signal
and T
runk Busy and the result code BUSY
.
NS is similar to the Common Operational Message
Invalid Number and the result code ERROR.
CB is similar to the Call Failure Messages, Dial Line in
Use and No Dial-T
est and the result code ERROR.
R
T is similar to the Call Failure Message No Answer
T
one and the result code NO CARRIER.
AB is similar to the Call Failure Messages, No Dial
Tone and No Dial-DTR and the result code NO
DIALT
ONE and ERROR.
NT is similar to the Call Failure Message No Quiet
Answer and the result code NO ANSWER.
Call Connecting (CNX)
The CNX response informs the DTE that the modem
has connected to the remote modem. CNX is similar to the
AT result code CONNECT.
The CNX response format is CNX.