7 Operation in Linux
7.2 Via TCP Raw Server Mode
The application will use the IP Address of the NetCom
+
with the configured TCP port number for
the intended serial port. Usually the first serial port uses 2001 as TCP data port, so as an example
program here is the command line for telnet application:
t e l n e t
1 9 2 . 1 6 8 . 1 . 2 4 9 2001
This command will open a raw TCP connection to the NetCom
+
. This connection is raw (no
modification of data) because there is no initiation of the protocol known as Telnet (RFC 854).
Every byte received on the serial port is displayed on the screen. And all characters typed on the
keyboard are sent via the serial port to the connected device. The serial parameters used are stored
in the NetCom
+
, e.g. 38400,8,n,1 without flow control. If RTS/CTS or a different mode of flow
control is configured, this is handled internally at the serial port inside the NetCom
+
.
Especially with telnet users often get confused by doubled characters on the screen. This is caused
by a misconfiguration of telnet, in this case the option of local echo. The typed character is shown
on the screen by telnet, and the serial device also sends back the character. The configuration of
telnet is beyond the scope of this manual.
Telnet is one example, other applications will use their own methods of configuation.
September 2016
NetCom Plus User Manual
95
Summary of Contents for NetCom Plus 111
Page 133: ......
