Contemporary Controls Metasys JC-MER-CXB, Руководство пользователя, Страница: 11 / 58

TD060100-0MA
11
The
JC-MER-CXB
program is accessed via COM
2
. The embedded
operating system is accessed via COM
1
. If a terminal emulation
program is attached to COM
2
, real-time routing statistics can be
observed. But once the router is started, no such cable
connection is
required for continued operation.
Theory of Operation
Setup and Addressing
The method of linking the two networks is to separate the N1 LAN
into a number of ARCNET subnets. (In this document, the terms
“subnet” and “ARCNET segment” are the same.) Each ARCNET
subnet then connects to the customer’s Ethernet network via a single
JC-MER-CXB
.
The router uses the N1 network addressing scheme to route messages
among the various ARCNET segments. Dividing Metasys into
multiple subnets has no affect on existing Ethernet communications,
and again, remains transparent to the operator.
To the operator, the router is simple to use and maintain. Once it is
configured to the customer’s network, the router works on its own,
uninterrupted. Branch office personnel configure the unit (via
HyperTerminal) by accessing a single screen. Once set, the data is
saved to a flash disk. Upon power up, the program and
configuration
data is executed without any intervention. There are
no moving
storage devices on the unit.
Protocols
The
JC-MER-CXB
uses the UDP/IP communications protocol to
transmit messages across the Ethernet network. This is important
because it allows the router to easily integrate into existing customer
networks that comprise multiple Internet (TCP/IP protocol
suite)
networks.