User's Manual

NPort W2150A/W2250A Series Web Console: Serial Port Settings
7-11
TCP alive check time
Default 7 min
Options 0 to 99 min
Description This field specifies how long the NPort will wait for a response to “keep alive” packets before
closing the TCP connection. The NPort checks connection status by sending periodic “keep
alive” packets.
0: The TCP connection will remain open even if there is no response to the “keep alive”
packets.
1 to 99: If the remote host does not respond to the packet within the specified time, the
NPort will force the existing TCP connection to close.
Inactivity time
Default 0 ms
Options 0 to 65535 ms
Description
This field specifies the time limit for keeping the connection open if no data flows to or from
the serial device.
0: The connection will remain open even if data is never received. For many applications, the
serial device may be idle for long periods of time, so 0 is an appropriate setting.
1 to 65535: If there is no activity for the specified time, the connection will be closed. When
adjusting this field, make sure that it is greater than the Force transmit time. Otherwise, th
e
TCP connection may be closed before data in the buffer can be transmitted.
Max connection
Default 1
Options 1 to 8
Description This field specifies the maximum number of connections that will be accepted by the serial
port.
1: Only one specific host can access this serial port, and the RealCOM driver on that host will
have full control over the port.
2 to 8: This serial port will allow the specified number of connections to be opened
simultaneously. With simultaneous connections, the RealCOM driver will only provide a pure
data tunnel with no control ability. The serial communication will be determined by the NPort
rather than by your application program. Application software that is based on the RealCOM
driver will receive a driver response of “success” when using any of the Win32 API functions.
The NPort will send data only to the RealCOM driver on the host. Data received from hosts will
be sent to the attached serial device on a first-in-first-out basis.
ATTENTION
When Max connection is 2 or greater, the serial port’s communication settings (i.e., baudrate, parity, data bits,
etc.) will be determined by the NPort. Any host that opens the COM port connection must use identical serial
communication settings.