NPort W2150A-W4/W2250A-W4 Series User Manual
71
IP Serial Library Introduction
What is IP Serial Library?
IP Serial Library is a Windows library with frequently used serial command sets and subroutines. IP Serial
Library reduces the complexity and poor efficiency of serial communication over TCP/IP. For example, Telnet
can only transfer data, but it can't monitor or configure the serial line's parameters.
Why Use IP Serial Library?
For programmers who are familiar with serial communication, IP Serial Library provides well-designed
function calls that have the same style as Moxa's PComm Library.
IP Serial Library is amazingly simple and easy to understand. By including it in your VB, C, or Delphi
programming environment, you can program your own TCP/IP application with the ability to control serial
communication parameters.
The NPort Serial Device Servers use 2 TCP ports for communication between the NPort and host computer's
Real COM driver. The NPort uses a data port and command port to provide pure data transfer without
decoding and encoding. Compared to using only one TCP port to control serial communication (such as RFC
2217), IP Serial Library uses a command port to communicate with NPort in user's program. IP Serial
Library not only runs with excellent efficiency, but also runs with no decoding or encoding problems.
You can find the usage of other functions in the subsection of
Real COM
mode in page 7-4.
Connection goes down
Default
always high
Options
always low, always high
Description
This field specifies what happens to the RTS and DTR signals when the Ethernet connection
goes down. For some applications, serial devices need to know the Ethernet link status
through RTS or DTR signals sent through the serial port.
Always low: The selected signal will change to low when the Ethernet connection goes
down.
Always high The selected signal will remain high when the Ethernet connection goes down.
Packet length
Default
0
Options
0 to 1024
Description
This field specifies the maximum amount of data that is allowed to accumulate in the serial
port buffer before sending.
0: Packet length is disregarded and data in the buffer will be sent as specified by the
delimiter settings or when the buffer is full.
1 to 1024: Data in the buffer will be sent as soon it reaches the specified length.
Delimiter 1 and 2
Default
Disabled
Options
Disabled, Enabled, 00 to FF
Description
These fields are used to define special delimiter character(s) for data packing. Enable
Delimiter 1 to control data packing with a single character; enable both Delimiter 1 and 2
to control data packing with two characters received in sequence.
When these fields are enabled, serial data will accumulate in the serial port’s buffer until
the buffer is full or until the specified delimiter character(s) are received. For example, the
carriage-return character could be used as a delimiter in order to transmit each sentence
or paragraph in a separate packet. Data will be packed according to Delimiter process.
Delimiters must be incorporated into the data stream at the software or device level.
