Moxa Technologies 5400 - Manual (Page 44)

At least, the Inactivity time should be set larger than that of Force Transmit timeout. To prevent the
unintended loss of data due to the session disconnected, it is highly recommended that this value is set
large enough so that the intended data transfer is completed.
Inactivity time is ONLY active when “TCP connection on” is set to “Any character.”
Delimiter 1
Setting Factory Default Necessity
00 to FF None Optional
Delimiter 2
Setting Factory Default Necessity
00 to FF None Optional
Once the NPort receives both delimiters through its serial port, it immediately packs all data currently
in its buffer and sends it to the NPort’s Ethernet port.
Delimiter 2 is optional. If left blank, then Delimiter 1 alone trips clearing of the buffer. If the size of
the serial data received is greater than 1K, the NPort will automatically pack the data and send it to
the Ethernet. However, to use the delimiter function, you must at least enable Delimiter 1. If Delimiter
1 is left blank and Delimiter 2 is enabled, the delimiter function will not work properly.
Force Transmit
Setting Factory Default Necessity
0 to 65535 ms 0 ms Optional
0: Disable the force transmit timeout.
1 to 65535: Forces the NPort’s TCP/IP protocol software to try to pack serial data received during the
specified time into the same data frame.
This parameter defines the interval during which NPort fetches the serial data from its internal buffer.
If there is incoming data through the serial port, NPort stores data in the internal buffer. NPort
transmits data stored in the buffer via TCP/IP, but only if the internal buffer is full or if the force
transmit time interval reaches the time specified as Force Transmit timeout.
Optimal force transmit timeout differs according to your application, but it must be at least as large as
one character interval within the specified baud rate. For example, assume that the serial port is set to
1200 bps, 8 data bits, 1 stop bit, and no parity. In this case, the total number of bits required to send a
character is 10 bits, and the time required to transfer one character is
10 (bits) / 1200 (bits/s) * 1000 (ms/s) = 8.3 ms.
Therefore, you should set Force Transmit timeout to be larger than 8.3 ms. Force Transmit timeout is
specified in milliseconds and must be larger than 10 ms.
If the user wants to send a series of characters in a packet, the serial device attached to NPort should
send characters without time delay larger than Force Transmit timeout between characters and the
total length of data must be smaller than or equal to NPort’s internal buffer size. The serial
communication buffer size of NPort is 1 Kbytes per port.
NPort 5400 Series User’s Manual 5-18