Moxa Technologies NPort 5400 - Manual (Page 23)

NPort 5400 Series User’s Manual Choosing the Proper Operation Mode
4-3
ATTENTION
The driver used for Real COM Mode comes with the NPort Windows Administrator. The driver
is installed automatically on your computer when you install NPort Administration Suite.
The important point is that Real COM Mode allows users to continue using RS-232/422/485 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 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’s serial ports.
ATTENTION
Real COM Mode allows several hosts to have access control over the same NPort. The driver
that comes with your NPort controls host access to attached serial devices by checking the host’s
IP address.
Modify the Accessible IP Setting table when the legal IP address should be required in your
application
TCP Server Mode
In TCP Server mode, NPort provides a unique IP:Port
address on a TCP/IP network. NPort waits passively to
be contacted by the host computer, allowing the host
computer to establish a connection with and get data
from the serial device. 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.
As illustrated in the figure, data transmission proceeds as
follows:
1. The host requests a connection from the NPort
configured for TCP Server Mode.
2. Once the connection is established, data can be
transmitted in both directions—from the host to the
NPort, and from the NPort to the host.