Table of Contents
Advertisement
18
Cn - Carrier Control
This command is included for compatibility only, and has no effect other than returning a
result code. The only valid parameter is 1.
Result Codes:
OK
n = 1.
ERROR
Otherwise.
Dn - Dial
This command directs the modem to go on-line, dial according to the string entered and
attempt to establish a connection. If no dial string is supplied, the modem will go on-line
and attempt the handshake in originate mode. In W-class models, the action of going off-
hook is affected by the status of the Line Current Sense input, if line current sensing is
enabled, and by the blacklist and delayed list.
NOTE: If the ATD command is issued before the S1 register has cleared, the modem will
respond with the NO CARRIER result code. Accordingly, with some country-specific regula-
tions, the modem will answer DELAYED when you are making repeated call attempts, without
getting any connection and BLACKLIST will be the answer if you are dialling a forbidden
number.
Dial Modifiers. The valid dial string parameters are described below. Punctuation charac-
ters may be used for clarity, with parentheses, hyphen, and spaces being ignored.
0-9
DTMF digits 0 to 9.
*
The 'star' digit (tone dialling only).
#
The 'gate' digit (tone dialling only).
A-D
DTMF digits A, B, C, and D. Some countries may prohibit sending of these
digits during dialling.
L
Re-dial last number: the modem will re-dial the last valid telephone number. The
L must be immediately after the D with all the following characters ignored).
P
Select pulse dialling: pulse dial the numbers that follow until a "T" is encoun-
tered. Affects current and subsequent dialling. Some countries prevent changing
of dialling modes after the first digit is dialled.
T
Select tone dialling: tone dial the numbers that follow until a "P" is encountered.
Affects current and subsequent dialling. Some countries prevent changing of dial-
ling modes after the first digit is dialled.
R
This command will be accepted, but not acted on.
S=n
Dial the number stored in the directory (n = 0 to 3 or 0 to 19 depending on the
modem model). (See &Z.)
!
Flash: the modem will go on-hook for a time defined by the value of S29. Coun-
try requirements may limit the time imposed.
W
Wait for dial tone: the modem will wait for dial tone before dialling the digits
following "W". If dial tone is not detected within the time specified by S6 the
modem will abort the rest of the sequence, return on-hook, and generate an error
message.
@
Wait for silence: the modem will wait for at least 5 seconds of silence in the call
progress frequency band before continuing with the next dial string parameter. If
the modem does not detect these 5 seconds of silence before the expiration of the
call abort timer (S7), the modem will terminate the call attempt with a NO AN-
SWER message. If busy detection is enabled, the modem may terminate the call
with the BUSY result code. If answer tone arrives during execution of this param-
eter, the modem handshakes.
Advertisement
Table of Contents
