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5.0 LocoNet: The Digitrax Difference!
5.1 System Architecture
System architecture is the biggest difference among layout con-
trol systems. System architecture is the way the components of
a control system communicate among themselves. Digitrax
LocoNet is a Peer to Peer local area network (LAN) designed
specifically for model railroad operation. LocoNet wiring is
cost effective, flexible and expandable to accommodate almost anything you
want to do with your railroad today and in the future.
The system architecture used for communication within DCC and other control
systems is not standardized. Therefore DCC compatibility encompasses only
decoders, command stations and boosters but not throttles and other devices.
In addition, devices that require feedback and other types of signals that are
outside the domain of DCC, such as detection systems and transponding, are
not standardized. LocoNet is a hybrid system that incorporates DCC and other
technologies to expand the capabilities of your system. Your Digitrax system
gives you the best of both worlds with a system that is compatible with today’s
DCC standards and also goes beyond those standards to deliver enhanced sys-
tem performance and advanced features that are far beyond the scope of DCC.
With Digitrax, it’s Complete Train Control!
5.2 event Driven or Polled?
LocoNet is an event driven network. The command station on LocoNet waits
for input from other components before sending commands to the layout. For
example, if there are 10 throttles on LocoNet and throttle #1 sends a command,
the command station sees it and executes immediately. With a distributed net-
work like LocoNet, new features can be added by simply plugging in new
hardware or software. Since LocoNet is a peer to peer network, devices on
LocoNet can act independently of the command station, too. Feedback is
incorporated in LocoNet’s communication scheme so you don’t need to wire a
separate feedback bus.
Other systems typically use polled buses or “networks.” In this case, the com-
mand station must “ask” each of the throttles or other devices in turn: “Do you
have input for me?” The device must wait for the command station to poll all
the devices on the bus before it sends the command. This arrangement can
slow down response times and limit the number of devices that can be handled
by the system as more and more devices are added. With centralized process-
ing in a master/slave control type system like this, adding new features usually
means updating the command station software when new components are
added since devices can’t operate on the system unless the master command
station knows how to handle them. To add feedback capabilities to this type of
system, a separate feedback bus may also be necessary.
