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Serial Port Profiles
Additional modem
initialization
You can specify additional virtual modem commands that will affect how
virtual modem starts. The following commands are supported: ATQn, ATVn,
ATEn, +++ATH, ATA, ATI0, ATI3, ATS0, AT&Z1, AT&Sn, AT&Rn, AT&Cn,
AT&F, ATS2, ATS12, ATO (ATD with no phone number), and ATDS1.
See Appendix C, Virtual Modem AT Commands for a more detailed
explanation of the support initialization commands.
Enable Message of
the Day (MOTD)
When enabled, displays the Message of the Day (MOTD) when a successful
virtual modem connection is made.
Default: Disabled
Enable TCP
Keepalive
Enables a per-connection TCP keepalive feature. After the configured number
of seconds, the connection will send a gratuitous ACK to the network peer, thus
either ensuring the connection stays active OR causing a dropped connection
condition to be recognized.
This parameter needs to be used in conjunction with Monitor Connection
Status Interval parameter found in the Serial, Advanced, Advanced Settings
tab. The interval specifies the inactivity period before "testing" the connection.
Default: Disabled
AT Command
Response Delay
The amount of time, in milliseconds, before an AT response is sent to the
requesting device.
Default: 250 ms
Session Strings Controls the sending of ASCII strings to serial devices at session start as
follows;
zSend at Start—If configured, this string will be sent to the serial device
on power-up of the IOLAN or when a kill line command is issued on this
serial port. If the "monitor DSR" or "monitor DCD" options are set, the
string will also be sent when the monitored signal is raised.
Range: 0-127 alpha-numeric characters
Range: hex 0-FF
zDelay after Send—If configured, will inset a delay after the string is sent
to the device. This delay can be used to provide the serial device with time
to process the string before the session is initiated or terminated.
Default: 10 ms