Moxa Technologies 5110 Series user manual UDP Mode, Real COM Mode, Pair Connection Mode

NPort 5110 Series User’s Manual Choosing the Proper Operation Mode

UDP Mode

Compared to TCP communication, UDP is faster and more efficient. In UDP mode, you can unicast or multicast data from the serial device to one or multiple host computers, and the serial device can also receive data from one or multiple host computers, making this mode ideal for message display applications.

Real COM Mode

NPort 5110 comes equipped with COM drivers that work with Windows 95/98/ME/NT/2000/XP systems, and also TTY drivers for Linux systems. The driver establishes a transparent connection between host and serial device by mapping the IP:Port of the NPort 5110 port to a local COM port on the host computer. This operation mode also supports up to 4 simultaneous connections, so that multiple hosts can collect data from the same serial device at the same time.

ATTENTION

The driver used for Real COM Mode is installed automatically on your computer when you install NPort 5110 Administration Suite.

One of the major conveniences of using Real COM Mode is that Real COM Mode allows users to continue using RS-232 serial communications software that was written for pure serial communications applications. The driver intercepts data sent to the host’s COM port, packs it into a TCP/IP packet, and then redirects it through the host’s Ethernet card. At the other end of the connection, the NPort 5110 accepts the Ethernet frame, unpacks the TCP/IP packet, and then transparently sends it to the appropriate serial device attached to one of the NPort 5110’s serial ports.

ATTENTION

Real COM Mode allows several hosts to have access control of the same NPort 5110. The driver that comes with your NPort 5110 controls host access to attached serial devices by checking the host’s IP address. Refer to Accessible IP Settings in Chapter 5 for more details.

Pair Connection Mode

Pair Connection Mode employs two NPort 5110 device servers in tandem, and can be used to remove the 15-meter distance limitation imposed by the RS-232 interface. One NPort 5110 is connected from its RS-232 port to the COM port of a PC or other type of computer, such as hand-held PDAs that have a serial port, and the serial device is connected to the RS-232 port of the other NPort 5110. The two NPort 5110 are then connected to each other with a cross-over Ethernet cable, both are connected to the same LAN, or in a more advanced setup, they communicate with each other over a WAN (i.e., through one or more routers). Pair Connection Mode transparently transfers both data and modem control signals (although it cannot transmit the DCD signal) between the two NPorts.

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