User manual

EKI-1521/1522/1524 User Manual 34
nections, so multiple hosts can transmit/receive data to/from the same serial port
simultaneously. Every host can transmit data to the same serial port, an
d the EKI-
152X series will also transmit data to every hosts. When the multiple hosts transmit
data to the same serial port at the same time, the received data from Ethernet and
the outputs of serial port are mixed. When the EKI-152X series receives data from
serial port, the data will also be transmitted to the connected hosts simultaneously.
 Round-Robin mode:
Enabling “Response Timeout” parameter, the EKI-152X series will operate in
“Round-Robin mode”. Each serial port supports up to five simultaneous connections,
so multiple hosts can transmit/receive data to/from the same serial port simulta-
neously. Every host can transmit data to the same serial port simultaneously, but the
EKI-152X series will process the data communication in order. The EKI-152X series
will process the first host’s request and reply the response to the first host. The EKI-
152X series serial device server can determine the end of the serial acknowledge-
ment via response timeout. When EKI-152X series serial device server receives
nothing from serial port after the setting of response timeout, the device will reply the
acknowledgement to the host and then process the next host’s request. While the
connected hosts are more and “Response Timeout” is long, the process time is much
longer.
Frame Break is a very import parameter for Round Robin mode. This parameter is
the smart way to reduce inefficient waiting time and the EKI-152X series can transmit
data more efficiently. Disabling the Frame Break function, the EKI-152X series will
wait “Response Timeout” period, whether the device have transmitted the data. Dur-
ing this period, the commands from hosts will be queued and the EKI-152X series
just processes this command. Enabling “Frame Break”, if the serial port idle is longer
than the “Frame Break” period, the EKI-152X series will assume the communication
is completed and continue the next host’s query. This is an efficient way to reduce the
waiting time and improve the performance.
3.5.2 Data Mode (USDG Mode)
The EKI-152X series can be Data server or Data client either. Both operations sup-
port TCP and UDP protocol. The EKI-152X series makes your serial devices behave
just like networking devices. You can issue commands or transmit data from serial
devices, which connected to the EKI-152X series, to any devices that are connected
to the Internet.
The EKI-152X series allows most 5 host PCs accessing data simultaneously via poll-
ing networking architecture. You can use it according to your application. If you want
to access the EKI-152X series, you must ascertain your application software sup-
ports standard networking application programming interface (API) such as: WinSock
Socket.
You might select “USDG Mode” as the following figure to change the mode of the port
to TCP server/client or UDP mode.