User`s manual

NPort 6000 Series User’s Manual Configuring Serial Port Operation Modes
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TCP alive check time (default=7 min): This field specifies how long the NPort 6000 will wait for
a response to “keep alive” packets before closing the TCP connection. The NPort 6000 checks
connection status by sending periodic “keep alive” packets. If the remote host does not respond to
the packet within the time specified in this field, the NPort 6000 will force the existing TCP
connection to close. For socket and device control modes, the NPort 6000 will listen for another
TCP connection from another host after closing the connection. If TCP alive check time is set to 0,
the TCP connection will remain open even if there is no response to the “keep alive” packets.
TCP port (default=4001): This is the TCP port number assignment for the serial port on the NPort
6000. It is the port number that the serial port uses to listen to connections, and that other devices
must use to contact the serial port. To avoid conflicts with well known TCP ports, the default is set
to 4001.
Packet length (default=0): The Packet length setting refers to the maximum amount of data that is
allowed to accumulate in the serial port buffer before sending. At the default of 0 for packet length,
no maximum amount is specified and data in the buffer will be sent as specified by the delimiter
settings or when the buffer is full. When a packet length between 1 and 1024 bytes is specified,
data in the buffer will be sent as soon it reaches the specified length.
Delimiter 1 and Delimiter 2 (default=None): When Delimiter 1 is enabled, the serial port will
clear the buffer and send the data to the Ethernet port when a specific character, entered in hex
format, is received. A second delimiter character may be enabled and specified in the Delimiter 2
field, so that both characters act as the delimiter to indicate when data should be sent.
ATTENTION
In order to enable a delimiter, packet length must be set to 0. Delimiter 2 should only be enabled
in conjunction with Delimiter 1 and never on its own; otherwise there may be data errors. Even
when a delimiter is enabled, the NPort 6000 will still pack and send the data when the amount of
data exceeds 1 KB.
Delimiter process (default=Do Nothing): The Delimiter process field determines how the data is
handled when a delimiter is received. Delimiter 1 must be enabled for this field to have effect. If
Delimiters 1 and 2 are both enabled, both characters must be received for the delimiter process to
take place.
y Do Nothing: Data in the buffer will be transmitted when the delimiter is received.
y Delimiter + 1: Data in the buffer will be transmitted after 1 additional byte is received following
the delimiter.
y Delimiter + 2: Data in the buffer will be transmitted after 2 additional bytes are received
following the delimiter.
y Strip Delimiter: Data in the buffer is first stripped of the delimiter before being transmitted.
Force transmit (default=0 ms): This parameter defines how large a gap in serial communication
the NPort 6000 will allow before packing the serial data in its internal buffer for network
transmission.
As data is received through the serial port, it is stored by the NPort 6000 in the internal buffer. The
NPort 6000 transmits data stored in the buffer via TCP/IP, but only when the internal buffer is full
or as specified by the force transmit time. When set to 0, the force transmit time is disabled, and
transmission is determined solely by the data in the internal buffer. At 1 to 65535, the TCP/IP
protocol software will pack the serial data received after there is a gap in serial communication
that exceeds the specified force transmit time.
The optimal force transmit time depends on your application, but it must be at least larger than one
character interval within the specified baudrate. For example, assume that the serial port is set to