“Client” connection settings

To configure advanced connection settings, please, activate Advanced mode by clicking the corresponding toolbar button. Now switch to “Connection prefs” tab, where you will see the following set of options:

If real port is used in connection:


1. “Open local real port only when connection is established” option permits to open local real serial port only when connection with the server side is established. It helps to keep the serial port free while there are no active connections available. This option is applicable only if real port is used in connection.

2. “Do not buffer size data for fast response” checkbox is used for disabling “Nagle algorithm” to achieve maximum speed of response if small packets are transmitted over network. Note, that this will increase traffic. If you are not sure, please, do not modify this option.

3. “On error retry to establish connection every” option permits to set a period of time in milliseconds after which Serial to Ethernet Connector will try to restore connection, if it was broken.

4. “Default port settings” option lets you manually assign predefined real port settings (for instance, if you have legacy serial port device that has specific parameters).

Real port settings can be also set automatically from the remote end, where virtual port is used for connection (if Telnet protocol is used).

This option is not available (grayed out) if you are creating virtual serial port since communication parameters are set by the application which opens the virtual port.

The following real port settings are available for configuration (read in “Server” connection settings” section in detail).

5. “Network protocol settings” option lets you choose the underlay protocol to be used for data transmission in your connection (read in “Server” connection settings” section in detail).

6. Send “Keep alive” every X sec … if no reply every Y sec

Send “Keep alive” option gives an interlocutor “Keep alive” command if there is no data transfer between the sides during X seconds. An interlocutor must respond to this message.

It permits to find possible connection problems and to maintain active connection. Use this option if your device disconnects automatically after a definite time of net inactivity.

Y is an interval of sending “Keep alive” message in case an interlocutor didn’t respond to the last “Keep alive” command sent with X sec interval.

7. Break connection if no activity for (sec)

SEC will break connection if no network activity is observed during the specified period of time.


If virtual port is used in connection:

Preferences for virtual port, used to create “client” connection, do not differ from that for real port, except for one option (see below). The rest of options are described in “If real port is used in connection” section above.“Connect to remote end only when local virtual port is open” checkbox enables SEC to make connection attempts only after virtual port is opened for communication by your application. If virtual port is closed, connection attempts will not be made. If this option is unchecked, connection attempts will be made regardless of status of local virtual port.