COMSPHERE 392xPlus Modems
D-2 November 1996 3920-A2-GN31-30
Call Request Commands
Call Request commands are issued from the DTE to the modem and are responsible for initiating
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:
CRN
n
Where: n is the telephone number to be dialed.

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:
CRS
x
Where: x is directory location 1–24.
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
A
Call Response indicates if the command was accepted by the modem. Call Response includes
Call Failure Indication (CFI) and Call Connecting (CNX).

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 DIALTONE, and
ERROR.
The CFI response format is:
CFIxx
Where: xx
is
ET Engaged tone.
NS Number not stored.
CB Local DCE busy.
RT Time-out on ring tone.
AB Abort call on time-out.
NT
Answer tone not detected.
FC Forbidden call.