User guide
Modem Emulation AT Command Set
Chapter 8 Modem Emulation 43
S-Registers
Register Function Range Units Saved Default
S0 Rings to Auto-Answer
Sets the number of rings required before the Digi Device Server automatically
answers a call. Setting this register to Zero disables auto-answer mode.
0-255 Rings * 0
S1 Ring Counter
S1 is incremented each time the modem detects a ring signal on the telephone
line. S1 is cleared if no rings occur over an eight second interval.
0-255 Rings 0
S2 Escape Character
S2 holds the decimal value of the ASCII character used as the escape character.
The default value corresponds to an ASCII ’+’. A value over 127 disables the
escape process, i.e., no escape character will be recognized.
0-255 ASCII * 43
S3 Carriage Return Character
Sets the command line and result code terminator character. Pertains to
asynchronous operation only.
0-127 ASCII 13
S4 Line Feed Character
Sets the character recognized as a line feed. Pertains to asynchronous operation
only. The Line Feed control character is output after the Carriage Return
control character if verbose result codes are used.
0-127 ASCII 10
S5 Backspace Character
Sets the character recognized as a backspace. Pertains to asynchronous
operation only. The modem will not recognize the Backspace character if it is
set to a value that is greater than 32 ASCII. This character can be used to edit a
command line. When the echo command is enabled, the modem echoes back to
the local DTE the Backspace character, an ASCII space character and a second
Backspace character; this means a total of three characters are transmitted each
time the modem processes the Backspace character.
0-32 ASCII 8
S6
Accepted but ignored.
2-255 s * 2
S7
Accepted but ignored.
1-255 s * 50
S8
Accepted but ignored.
0-255 s * 2
S9
Accepted but ignored.
1-255 0.1 s * 6
S10
Accepted but ignored.
1-255 0.1 s * 14
S11
Accepted but ignored.
50-255 0.001 s * 95
S12 Escape Prompt Delay
Defines the maximum period, in fiftieths of a second, allowed between receipt
of the last character of the three escape character sequence from the DTE and
sending of the OK result code to the DTE. If any characters are detected during
this time, the OK will not be sent. Note that sending of the OK result code does
not affect entry into command mode.
0-255 0.02 s * 50
S13 Reserved - - -