User's Manual

NPort W2150A/W2250A Series Web Console: Serial Port Settings
8-10
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, the 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 Real COM 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 Real COM 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 Real COM driver will receive a driver response of “success” when using any of the
Win32 API functions. The NPort will send data only to the Real COM 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 two 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.