MLis MLB-S4101, User Manual

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MLiS-S4101 Manual
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2 Communication Modes
The MLB-S4101 allows serial devices to communicate over a LAN or Intranet network. Serial devices are no longer
limited to a physical connection to the PC COM port. They can be installed anywhere on the LAN using TCP/IP or UDP/IP
communications. This will also allow traditional PC COM ports access to a serial device anywhere on the LAN network.
2.1 Direct IP Mode
Direct IP connections allow applications using TCP/IP or UDP/IP network socket programs to communicate with the
asynchronous serial port on the MLB-S4101. In this type of application the MLB-S4101 is configured to TCP or UDP
server. The socket program running on the PC establishes a communication connection with the MLB-S4101. The raw
data is sent directly to and from the serial port.
2.2 Virtual COM Mode
The Virtual COM mode requires the installation of a driver. When installed a new COM port is added to the Device
Manager. Windows programs using standard Windows API calls will be able to interface with Virtual ports. The PC will act
as the host connecting to the MLB-S4101 when the program opens the virtual COM port.
Once the connection is made, the LAN is transparent to the serial device. Applications work just as if the serial device is
connected a host’s physical COM port. The virtual COM port converts the application’s data into IP packet destined for the
MLB-S4101, which in turn converts the IP packet back to serial data.
In this mode, the MLB-S4101 must be set to either TCP/server or UDP/server in the menu with a designated
communication port number. The virtual COM driver is a TCP or UDP client.
2.3 Paired Mode
Paired mode is also called serial tunneling. When this type of configuration is selected additional software will not have to
be loaded on a host PC. In fact a PC is not required to make the connection. Any two dumb serial devices that can
communicate with each other through a serial link will be able to communicate using two MLB-S4101s and the LAN.
Two MLB-S4101s are configured with one setup as a TCP or UDP client and the other to TCP/UDP server. When setting
up the Server, the Remo
te IP address section must contain the address of the Client. This will allow the Client’s IP
address to pass the IP address-filtering feature of the Server. Conversely, the Remote IP address of the Client must
contain the Server’s IP address.