Appendix
AT commands
S−register
l
79
EDSMF2181IB EN 3.0
10.3.6
S−register
Certain modem values or parameters are stored in memory locations, the so−called
S−registers. Use the S−commands (not described in this manual) to read or alter the
contents of S−registers (see previous section). *Register values can be stored on one of two
user profiles by means of the &W−command.
Register Unit
Range
Default
setting
Description
S0
1 bell
signal
0 − 255
0
Number of bell signals to the automatic response:
Sets the number of bell signals until the modem responds. ATS0=0
completely deactivates the automatic response. *
S3
Decimal 0 − 127
13 (^M)
Carriage return character:
Defines the command line and the end character of the result code.
Only refers to asynchronous operation.
S4
Decimal 0 − 127
10 (^J)
Line feed character:
Defines the character that is identified as line feed. Only refers to
asynchronous operation. The line feed control character is output after
the return control character if long result codes are used.
S6
Seconds 2 − 255
2
Waiting time before blind dialling or for dial tone:
1. Defines the time in seconds for which the modem waits before it
starts dialling after it has answered at blind dialling. This operation,
however, can be influenced by some ATX options specified by
country restrictions. The "waiting for dial tone" call progress feature
(W−dial modifier in the dial string) overwrites the value in register
S6 (if configured for the USA).
2. Defines the time in seconds for which the modem waits for the dial
tone if it detects a "W" dial modifier and before it reports a NO DIAL
TONE result code. (W class). The default setting depends on the
respective country. The modem always pauses for at least 2
seconds, even if the value of S6 is less than 2 seconds. *
S7
Seconds 1 − 255*
50
Waiting time for carrier, silence or dial tone:
1. Defines the time in seconds for which the modem waits for the
carrier before it hangs up. The timer is started when the modem
stops the dialling process (originate), or 2 seconds after it has
answered (respond). In "Originate" mode, the timer is always reset
when an answer tone is detected, if this is permitted by the country
restrictions.
2. Defines the time in seconds for which the modem waits for silence
if it encounters the @ dial modifier before it continues with the
next dial string parameter.
3. Defines the time in seconds for which the modem waits for the dial
tone if it encounters a "W" dial modifier before it continues with
the next dial string parameter (USA model). The default setting
depends on the respective country. *
S8
Seconds 2 − 255
2
Pause for dial delay:
Defines the time in seconds for which the modem must pause if it
encounters the "," dial modifier in the dial string. *
S10
0.1 s
1 − 255
14
Lost carrier for hang up delay:
Defines the time in tenths of a second for which the modem waits
before it hangs up after a loss of the carrier. This allows for a
temporary carrier loss without the local modem cancelling the
connection. If register S10 is set to 255, the modem works as if a carrier
is always present. *
The current time period for which the modem waits before it cancels
the connection is the value in register S10 minus the value in register
S9. Therefore the S10 value must be greater than the S9 value, or the
modem cancels the connection before it detects the carrier.
Note: The following applies to the call waiting detection. If the modem
is set to the USA country code and S10 >=16, the modem detects the
call waiting tone and hangs up. If S10 <16, the modem does not detect
the call waiting tone.
* Register values can be stored on one of the two user profiles with the &W commands.