(+++) The Escape Code
The escape code returns the modem to the command state from the online state, without
releasing the telephone line. This command consists of an escape guard time (S12 default
1 second) and an escape character (ASCII code in S2 default '+'). The escape character
must be issued three consecutive times with a guard time before and after the characters.
If the sequence is successful, the modem responds 'OK' and enters an 'escape' command
state.
(&Cn) DCD Options
&C or &CO maintains a DCD ON condition and ignores the actual state of the data
carrier from the remote modem. &C1 (default) causes DCD to reflect remote carrier
status.
(&Dn) DTR Options
&D or &DO causes the modem to ignore DTR. After the &D1 command the modem will
go from data mode to command state on an ON to OFF transition of DTR. For &D2
(default) an ON to OFF transition of DTR will cause the modem to go on-hook, disable
auto-answer, and end in the command state. &D3 causes the modem to reset (see Zn
command) if it detects an ON to OFF transition of DTR. DTR transitions during idle state
will not generate any result codes or have any other effect on the modem.
- Any ON to OFF state change in DTR must last longer than the period specified by S25
in order to be recognized.
