Pack Control
Two firmware-selectable packing algorithms define how and when packets are sent to the
network. The standard algorithm is optimized for applications in which the unit is used in a
local environment, allowing for very small delays for single characters, while keeping the
packet count low. The alternate packing algorithm minimizes the packet count on the network
and is especially useful in applications in a routed Wide Area Network (WAN). Adjusting
parameters in this mode can economize the network data stream.
Pack control settings are enabled in Flush Mode. Set this value to
00
if you do not need
specific functions.
Pack Control Options
Packing Interval:
Packing Interval defines how long the unit should wait before sending
accumulated characters. This wait period is between successive network segments containing
data. For alternate packing, the default interval is 12 ms.
Trailing Characters:
In some applications, CRC, Checksum, or other trailing characters
follow the end-of-sequence character; this option helps to adapt frame transmission to the
frame boundary.
Send Characters:
If 2-Byte Send Character Sequence is enabled, the unit interprets the
sendchars as a 2-byte sequence; if this option is not enabled, the unit interprets them
independently.
If Send Immediately After Characters is
not
set, any characters already in
the serial buffer are included in the transmission after a "transmit" condition is found. If this
option is set, the unit sends immediately after recognizing the transmit condition (sendchar or
timeout).
Note:
A transmission might occur if status information needs to be exchanged or an
acknowledgment needs to be sent.
DisConnTime (Inactivity Timeout)
Use this parameter to set an inactivity timeout. The unit drops the connection if there is no
activity on the serial line before the set time expires. Enter time in the format mm:ss, where m
is the number of minutes and s is the number of seconds. To disable the inactivity timeout,
enter
00:00
. Range is 0 (disabled) to 5999 seconds (99 minutes, 59 seconds). Default is 0.
Send Characters
You can enter up to two characters in hexadecimal representation in sendchar. If the unit
receives a character on the serial line that matches one of these characters, it sends the
character immediately, along with any awaiting characters, to the TCP connection. This action
minimizes the response time for specific protocol characters on the serial line (for example,
ETX, EOT). Setting the first sendchar to
00
disables the recognition of the characters.
Alternatively, the unit can interpret two characters as a sequence (see
Pack Control
above).
