Configuration and setup
Wieland Electric GmbH | BA000870 | 06/2020 (Rev. A)
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Delimiters
•
Serial to Network Packet Delimiter:
Packet delimiter is a way of packing data in the serial com-
munication. It is designed to keep packets intact.
wienet SDS
provides three types of delimiter:
Time Delimiter
,
Maximum Bytes
and
Character Delimiter
. Note that the following delimiters
(Interval, Max Byte and Character) when they are selected are programmed in the OR logic.
Meaning that if any of the three conditions were met, the device would transmit the serial data
in its buffer over the network.
◦
Interval timeout:
wienet SDS
will transmit the serial data in its buffer when the specified
time interval has reached and no more serial data comes in. The default value is calculated
automatically based on the baud rate which is the
Auto (calculate by baud rate)
option. If
the automatic value results in chopped data, the timeout could be increased manually by
switching to
Manual setting
(checking the radio button in Figure 18) and specifying a larger
value in the text box above. Note that the maximum interval is 30,000 milliseconds.
Manual calculation of Interval timeout
The optimal
Interval timeout
depends on the application, but it must be at least larger than one-
character interval within the specified baud rate.
For example, assuming 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 (included 1 start bit), and the
time required to transfer one character is (10 (bits)/1200 (bits/s))*1000 (ms/s) = 8.3 ms.
Therefore, you should set the "Interval timeout" to be larger than 8.3 ms. Rounding 8.3 ms to the
next integer would give you 9 ms. Which can be set as your interval timeout.
◦
Max Bytes:
wienet SDS
will transmit the serial data in its buffer when the specified length in
the unit of bytes has reached. The range of maximum bytes is between 1 to 1452 bytes. Ena-
ble this option by checking the box in front of
Max. Bytes
, if you would like
wienet SDS
to
queue the data until it reaches a specific length. This option is disabled by default.
◦
Character:
wienet SDS
will transmit the serial data in its buffer when it sees the incoming
data that includes the specified character (in hexadecimal (HEX) format). This field allows
one or two characters. If character delimiter is set to 0x0d,
wienet SDS
will push out its serial
buffer when it sees 0x0d (carriage return) in the serial data. This option is disabled by de-
fault.
•
Network to Serial Packet Delimiter:
This group of options is the same as the delimiters de-
scribed above, but they control data flow in the opposite direction.
wienet SDS
will store data
from the network interface in its queue. Until one of the delimiter conditions described above is
met then device will send the data over to the serial interface.
•
Response Interval Timeout:
This option only affects the
Request & Response Mode
and has no
effect on the
Transparent Mode
. When TCP data is received (a request from network) and
passed to serial device side, the
wienet SDS
will wait for the set time before transferring another
TCP data if the serial device side did not receive any data (no response from the serial device).
The maximum value for this option is 60,000 milliseconds or 1 minute.
Serial
•
Serial FIFO:
By default,
wienet SDS
has its First-In-First-Out (FIFO) function enabled to optimize
its serial performance. In some applications (particularly when the flow control mechanism is
enabled), it may be necessary to disable the FIFO function to minimize the amount of data that
is transmitted through the serial interface after a flow off event is triggered to reduce the possi-
bility of overloading the buffer inside the serial device. Please note that disabling this option on
baud rates higher than 115200bps would noticeably reduce the data integrity.
•
Serial Buffer:
By default,
wienet SDS
will empty its serial buffer when a new TCP connection is
established. This means that the TCP application will not receive buffered serial data during a
TCP link breakage. To keep the serial data when there is no TCP connection and send out the
buffered serial data immediately after a TCP connection is established, you can disable this op-
tion.
After finishing the configuration of the COM Port's
Advanced Settings
, please click on
Save & Apply
to keep the change that you have made. Then, the
Advanced Settings
browser window can be
closed by clicking on
Close
button and you will be returned to
COM 1 Port Setting
page.
NOTI C E