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The
Microlon controller combines the power of LONWORKS technology with
Grayhill standard industrial I/O racks and modules. Microlon controllers
may be distributed over great distances yet provide seamless interoperability.
The robust communication protocol LonTalk is built into the firmware
of the Neuron chip, the heart of LONWORKS technology. The LonTalk
protocol follows the (7 layer) OSI Reference Model for network protocols.
This technology is becoming the de facto standard for interoperability.
This frees the user from worrying about network communication protocols.
DETAILS
In applications where the inputs and outputs that need to be monitored
and controlled are spread out over a large area, running long signal
lines from the sensors and actuators to a central controller can
lead to numerous costly problems. First, there is the time and expense
of routing the signal lines and shielding them from cross-talk,
EMI, and RFI. If this is not done properly, the cost and time required
to trouble-shoot the wiring can be exorbitant. Finally, making a
change to the system after installation is costly.
To alleviate
this problem, install Microlon units and I/O modules near the sensors
or actuators and network the Microlon units back to the host computer
(if a host is necessary). Peer-to-peer communications, inherent
with LONWORKS technology, make it easy to extend signals digitally,
without signal loss.
Up to 63 Microlon
controllers (nodes) can be networked together on a physical segment.
Units can be added with the aid of repeaters or routers. Each node
may contain up to 8 isolated modules, configured as input or output,
digital or analogue.
Microlon controllers
use one of three different physical media types to communicate over
the network. Twisted pair, transformer isolated (TP/ XF) networks
operate at 78 Kbps or 1.25 Mbps at distances up to 6500 feet (2000
meters) and 1600 feet (500 meters) respectively. In addition, FTT-10
operating at 78 Kbps at distances up to 1500 feet (500 meters) is
supported. Routers and Bridges may be used to change the communication
media type from node to node. For example, a Router may connect
a group of nodes operating over the FTT-10 medium to another group
utilising the TPT-XF/1250 medium.
Networks are
installed and/or modified using the Echelon LonBuilder Development
system, LonMaker installation tool or a third party tool.
LonMaker is a software package that runs on any PC and communicates
to Microlon controllers using a Serial LonTalk Adapter (SLTA) or
a PC Lontalk Adapter (PCLTA). SLTAs are available for all types
of network media and converts them to RS-232 at speeds up to 115,200
baud. PCLTAs are ISA-bus cards that offer higher performance. If
the network contains other LONWORKS based products, the NetProfiler
(included with LonMaker) is used to define the "parts catalogues"
tailored to the network. Otherwise, for networks containing only
Microlon controllers, the "parts catalogue" will be provided,
eliminating the need for the NetProfiler package. Third party network
management, control and monitoring tools and LonTalk Adapters are
available, please contact Gemlog for more information.
The Microlon
controller is shipped with a standard application program which
contains everything necessary to interface with all of Grayhill's
I/O modules. Installation, configuration, and trouble-shooting are
outlined in the 72-LON-18 manual (order separately). In addition,
the Microlon application disk is supplied with the manual and contains
example source code and the interface files ("parts catalogue").
The readme file contains information not found in this manual. If
you have a LonBuilder or NodeBuilder Development Tool, you may wish
to modify the application program and tailor it to your application.
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