4.5.4.A Serial Communication (continued)
Transceiver: Can either be set to
Modbus/TCP: A widely used protocol mainly in industrial automation applications with default TCP port number of 502 (see Local Port field). The options are Enable and Disable. If enabled, the Modbus/TCP is the only protocol driven by the iServer on its LAN port. If disabled, the TCP/IP is the only protocol driven by the iServer on its LAN port (default is disable).
End Character: When the defined Hex character is received by the iServer on its serial port, the iServer will forward the buffered serial data to the Ethernet. The default value is 00, which forces the iServer to forward the data to the Ethernet as it receives the data on its serial port (this means that the iServer requires NO “end character” to forward the data).
Forward End Char: If enabled, the iServer will send the End Character out to the Ethernet as part of the data. If disabled, the iServer will not count the End Character as part of the data and will drop it (default is enabled.)
Timeout: In RS232 connection, if the iServer does not receive any more serial data within the given time value, the iServer will forward the buffered serial data to the Ethernet. For example, if the Timeout is set to 200 ms, the iServer will send out the buffered serial data to the LAN, if it does not receive any more data on its serial port for a period of 200 ms.
In RS485 connection, the Timeout value is used to switch between serial transmit and receive mode. Since the iServer supports
4.5.4.B Terminal Server
TCP/UDP: The iServer supports TCP and UDP protocol (default is TCP). If UDP is selected, it can be configured either for Broadcast UDP or Directed UDP. In case of Broadcast UDP, the iServer will transmit the serial data to every node on the network. This can be accomplished if the Remote IP Address is set to 255.255.255.255.
The Broadcast UDP is a practical solution when one device needs to communicate with multiple PC’s or devices over the network
Server Type: In most cases the iServer will be acting as a Slave device. Slave option is chosen when a network host needs to connect to the serial port of the iServer (default is Slave)
Number of Connections: The range is from 0 to 5. If 0 is selected, the Terminal Server feature is disabled. That means that no network connection can be made to the serial port of the iServer. If 1 is selected, only one network connection can be made to the iServer’s serial port. Any number more than 1 would allow the network hosts to monitor (read only) the traffic on the iServer’s serial port simultaneously, but only one network host would be allowed to read and write (default is 0).
Local Port: This is the port or socket number for the iServer’s serial port. Any number between 500 and 9999 can be defined with the exceptions of 1000 and 2002 which are already used by the iServer for other purposes.
If the “Number of Connections” is set to 0, the iServer’s “Local Port” will be 1000, regardless of the displayed value inside the “Local Port” box. Once the “Number of Connections” is changed to a
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