Moxa Technologies IA5150 - Manual (Page 39)

NPort IA5150/5250 Series User’s Manual Web Console Configuration
5-14
ATTENTION
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 1 KB, the NPort IA5150/5250 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.
Delimiter process
Setting Factory Default Necessity
Do nothing
Delimiter + 1
Delimiter + 2
Strip Delimiter
Do Nothing Optional
[Delimiter + 1] or [Delimiter + 2]: The data will be transmitted when an additional byte (for
Delimiter +1), or an additional 2 bytes (for Delimiter +2) of data is received after receiving the
Delimiter.
[Strip Delimiter]: When the Delimiter is received, the Delimiter is deleted (i.e., stripped), and the
remaining data is transmitted.
[Do nothing]: The data will be transmitted when the Delimiter is received.
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 IA5150/5250’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 time interval during which NPort IA5150/5250 fetches the serial data
from its internal buffer. If data is incoming through the serial port, NPort IA5150/5250 stores the
data in the internal buffer. NPort IA5150/5250 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
under Force transmit timeout.
The optimal Force transmit timeout depends on your application, but it must be at least larger than
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 needed 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, so in this case, it must
be greater than or equal to 10 ms.
If the user wants to send a series of characters in the same packet, the serial device attached to
NPort IA5150/5250 should send that series of characters during a time interval less than the Force
transmit timeout for NPort IA5150/5250, and the total length of data must be less than or equal to
NPort IA5150/5250’s internal buffer size. The serial communication buffer size for NPort
IA5150/5250 is 1 KB per port.