Serge NOEL
1301 lines
57 KiB
Plaintext
1301 lines
57 KiB
Plaintext
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<meta name="generator" content="HTML Tidy for HTML5 for Apple macOS version 5.8.0">
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<title>JMRI Hardware Support - Standalone LocoNet®</title>
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<meta name="author" content="B. Milhaupt">
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<meta name="keywords" content=
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"Digitrax LocoNet BDL16 BDL162 BDL168 DS64 PR3 DCS100 DB150 JMRI LocoBuffer-USB LocoBuffer-II LocoBuffer FastClock">
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<div id="mBody">
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<!--#include virtual="Sidebar.shtml" -->
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<div id="mainContent">
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<h1>Hardware Support: Standalone LocoNet®</h1>
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<h2>Contents</h2>
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<ul>
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<li>
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<a href="#generalideas">Introduction</a>
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</li>
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<li>
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<a href="#jmriconfig">JMRI Configuration</a>
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</li>
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<li>
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<a href="#hwconsider">Hardware Considerations</a>
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<ul>
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<li>
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<a href="#dataterm">LocoNet Data Signal "Termination"</a>
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<ul>
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<li>
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<a href="#hwdataterm">Some commercial hardware which can provide LocoNet Data
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signal termination</a>
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</li>
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<li>
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<a href="#diyhwdataterm">Do-it-yourself LocoNet Data signal termination</a>
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</li>
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</ul>
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</li>
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<li>
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<a href="#railsyncgen">LocoNet RailSync Signal "Generation"</a>
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<ul>
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<li>
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<a href="#hwdctorailsync">Some commercial hardware which can provide DC power to
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the LocoNet RailSync wires</a>
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</li>
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<li>
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<a href="#rspowersupply">RailSync power from a DC power supply</a>
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</li>
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<li>
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<a href="#rsfromdtcs">RailSync from a Digitrax command station</a>
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</li>
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<li>
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<a href="#rsfromnondtcs">RailSync from a non-Digitrax command station</a>
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<ul>
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<li>
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<a href="#rsfromncecs">RailSync from an NCE command station</a>
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</li>
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</ul>
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</li>
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</ul>
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</li>
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<li>
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<a href="#pseudoground">BDL16x connection to a DCC system without a "Ground"
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terminal</a>
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</li>
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<li>
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<a href="#multipleconnections">Multiple active LocoNet connections</a>
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<ul>
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<li>
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<a href="#routeconnprefix">Routing LocoNet messages to a LocoNet connection based
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on "Connection Prefix"</a>
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</li>
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<li>
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<a href="#routeConName">Routing LocoNet messages to a LocoNet connection based on
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"Connection Name"</a>
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</li>
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<li>
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<a href="#routedefault">Routing LocoNet messages to a LocoNet connection based on
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"Default" settings</a>
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</li>
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<li>
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<a href="#multconsingle">Multiple active LocoNet connections to a single
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LocoNet</a>
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</li>
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</ul>
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</li>
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<li>
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<a href="#sneakpaths">"Sneak paths" and Computer Interfaces</a>
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</li>
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</ul>
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</li>
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<li>
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<a href="#examples">Standalone LocoNet® Examples</a>
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<ul>
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<li>
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<a href="#isolthrdetsig">Isolating the LocoNet throttle bus from LocoNet Turnouts,
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Detection & Signaling</a>
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</li>
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<li>
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<a href="#bdl168wnondtcs">Switches (DS64), Detection (BDL168) and Signals (SE8C) with
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non-Digitrax DCC command station</a>
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</li>
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<li>
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<a href="#se8csigwodtcs">SE8C signaling without a Digitrax command station</a>
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</li>
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</ul>
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</li>
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<li>
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<a href="#acknowledgments">Acknowledgments</a>
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</li>
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<li>
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<a href="#references">Documentation</a>
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</li>
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</ul>
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<h2 id="generalideas">Introduction</h2>
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<p>A "Standalone" LocoNet® is a LocoNet bus which does not have a LocoNet command station.
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Since it does not have a LocoNet command station, it cannot control locomotives, and cannot
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directly influence the DCC track signal created by a DCC command station.</p>
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<p>There are several situations where a standalone LocoNet bus is useful. Some of these
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situations are listed here:</p>
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<ul>
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<li>When using LocoNet peripherals with a non-LocoNet DCC command station.</li>
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<li>When using LocoNet peripherals with a non-DCC railroad.</li>
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<li>To isolate LocoNet peripherals from LocoNet throttle activity.</li>
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<li>To avoid LocoNet traffic issues associated with the Digitrax command station's small
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buffer for forwarding LocoNet switch commands to the DCC track signal.</li>
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<li>Some users even find it useful to have JMRI communicate with two or more LocoNet
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connections. One LocoNet connection might be a "standard" LocoNet, with a LocoNet-based
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command station, so that JMRI can program decoders and perhaps control mobile decoders.
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Another LocoNet connection could be a standalone LocoNet, with block detection, signal
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control, and switch control hardware monitored and controlled by JMRI. This standalone
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LocoNet is quite useful when implementing a CTC panel, as it ensures that the block
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detection and signaling cannot be influenced by throttle activity. In other words, a
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LocoNet throttle user might send LocoNet switch control messages, but those messages won't
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have any effect on the switches and/or signals which are on the standalone LocoNet.</li>
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</ul>
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<p>This page gives some general suggestions for implementing a standalone LocoNet as well as
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suggestions for configuring JMRI software to make use of the standalone LocoNet.</p>
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<h2 id="jmriconfig">JMRI Configuration</h2>
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<p>For JMRI to communicate with an independent LocoNet, the JMRI computer requires one
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LocoNet adapter device per independent LocoNet. Each adapter is configured on a separate JMRI
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"Connection" within the JMRI "Connections" tab settings under JMRI "Preferences". Each
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connection should be configured following the general instructions found at the <a href=
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"Digitrax.shtml">JMRI Hardware Guide: Digitrax DCC</a> page.</p>
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<p>Except as noted below for the <a href="#PR3config">PR3</a>, the JMRI connection for the
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standalone LocoNet should specify the "<code>Command Station type</code>" of
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"<code><strong>Stand-alone LocoNet</strong></code>".</p>
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<p>A standalone LocoNet will typically not control the hardware resources associated with
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"throttle management", "track power management", "command station management", and will
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typically not provide a programming track. As such, a standalone LocoNet connection will
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typically not be associated with "Throttles", "Power Control", "Command Station", or
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"Programmer" on the "Default" pane of the JMRI "Preferences" panel.</p>
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<h2 id="hwconsider">Hardware Considerations</h2>
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<p>A "LocoNet" bus implementation which has all the electrical signaling required by all
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LocoNet devices requires a LocoNet-based command station, such as the Digitrax DCS100 or
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Digitrax DB150. Some applications do not need all of the functionality provided by the
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Digitrax command station. This is where the standalone LocoNet bus is useful.</p>
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<p>Different LocoNet devices require different features of LocoNet". Key LocoNet features
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which are normally provided by a LocoNet-based command station include: "Slot management",
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"RailSync" signal, LocoNet Data signal termination, and fast clock master. The table below
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shows some LocoNet devices and their requirements.</p>
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<table class="wide">
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<tr>
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<th colspan="5">Command Stations and Boosters</th>
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</tr>
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<tr>
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<th>Device</th>
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<th>Slot Management</th>
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<th>RailSync</th>
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<th>LocoNet Data signal termination</th>
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<th>Fast Clock Master</th>
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</tr>
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<tr class="ctr">
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<td>
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Digitrax command stations
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<ul>
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<li>DB150</li>
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<li>DCS100/DCS200</li>
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<li>DCS50/DCS51/DCS52</li>
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<li>DCS240/DCS240+</li>
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<li>DCS210/DCS210+</li>
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</ul>
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</td>
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<td>Provides</td>
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<td>Provides DCC signal</td>
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<td>Provides</td>
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<td>Provides</td>
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</tr>
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<tr class="ctr">
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<td>
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Digitrax boosters
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<ul>
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<li>DB150</li>
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<li>DCS100/DCS200</li>
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<li>DCS240/DSC240+</li>
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<li>DCS210/DCS210+</li>
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<li>DCS50/DCS51/DCS52</li>
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<li>DB210/DB210Opto/DB220</li>
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</ul>
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</td>
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<td>
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</td>
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<td>Requires DCC signal</td>
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<td>
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</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Uhlenbrock Intellibox</td>
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<td>Provides</td>
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<td>Can provide DCC signal ****</td>
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<td>Provides</td>
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<td>?</td>
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</tr>
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<tr class="ctr">
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<td>Uhlenbrock Daisy System (Daisy<br>throttle plus Powerxx booster<br>or Daisy II Zentrale<br>)</td>
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<td>Provides</td>
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<td>Can provide a DCC signal *</td>
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<td>Provides</td>
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<td>?</td>
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</tr>
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<tr class="ctr">
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<td>Non-LocoNet command station</td>
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<td>
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</td>
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<td>Can provide DCC signal *</td>
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<td>Provides?</td>
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<td>Provides?</td>
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</tr>
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<tr>
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<th colspan="5">Computer Interface Devices</th>
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</tr>
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<tr>
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<th>Device</th>
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<th>Slot Management</th>
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<th>RailSync</th>
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<th>LocoNet Data signal termination</th>
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<th>Fast Clock Master</th>
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</tr>
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<tr class="ctr">
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<td>Digitrax PR3 (in MS100 mode)</td>
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<td>Optional</td>
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<td>
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</td>
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<td>Required, can provide</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Digitrax PR4 (in MS100 mode)</td>
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<td>Optional</td>
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<td><em>Requires DCC signal or simple power supply *****</em>
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</td>
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<td>Required, <em>cannot provide</em></td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>RR-CirKits LocoBuffer-USB Rev N,<BR>LocoBuffer-USB Rev O, LocoBuffer-NG</td>
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<td>Optional</td>
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<td>Required for power **</td>
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<td>Required, <em>cannot provide</em></td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>RR-CirKits LocoBuffer-II/LocoBuffer-USB</td>
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<td>Optional</td>
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<td>Required for power **</td>
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<td>Required, can provide</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>LocoBuffer</td>
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<td>Optional</td>
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<td>
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</td>
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<td>Required, might provide ***</td>
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<td>
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</td>
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</tr>
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<tr>
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<th colspan="5">LocoNet Throttles</th>
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</tr>
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<tr>
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<th>Device</th>
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<th>Slot Management</th>
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<th>RailSync</th>
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<th>LocoNet Data signal termination</th>
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<th>Fast Clock Master</th>
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</tr>
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<tr class="ctr">
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<td>Digitrax DT100x/DT200x/DT300x/<br>DT400x/DT402x/DT500x/DT602x/UTx throttle</td>
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<td>Required</td>
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<td>Optional, for power</td>
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<td>Required</td>
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<td>Optional</td>
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</tr>
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<tr>
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<th colspan="5">Some Other LocoNet Devices</th>
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</tr>
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<tr>
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<th>Device</th>
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<th>Slot Management</th>
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<th>RailSync</th>
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<th>LocoNet Data signal termination</th>
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<th>Fast Clock Master</th>
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</tr>
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<tr class="ctr">
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<td>Digitrax LNRP, LNRP3</td>
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<td>
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</td>
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<td>Requires DCC signal</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Digitrax DS54/DS64/DS74/DS78V</td>
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<td>
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</td>
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<td>
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</td>
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<td>Required if connected to LocoNet</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Digitrax BDL16/BDL162/BDL168</td>
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<td>
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</td>
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<td>Requires DCC signal</td>
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<td>Required, can provide</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Digitrax BDL716</td>
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<td>
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</td>
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<td>Requires DCC signal</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Digitrax PM4/PM42</td>
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<td>
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</td>
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<td>Requires DCC signal</td>
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<td>Required, can provide</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Digitrax PM74</td>
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<td>
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</td>
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<td>Requires DCC signal</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Digitrax SE74</td>
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<td>
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</td>
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<td>
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</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Digitrax UR90/UR90X/UR91/UR92/UR92CE/UR93</td>
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<td>Required</td>
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<td>
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</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Digitrax BXP88</td>
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<td>
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</td>
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<td>Requires DCC signal</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Digitrax BXPA1</td>
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<td>
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</td>
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<td>Requires DCC signal</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Digitrax LNWI</td>
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<td>Required</td>
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<td>
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</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>(DIY)LocoIO/LocoServo</td>
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<td>
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</td>
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<td>
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</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>Team Digital SIC24/SIC24AD/SRC8/SRC16/SC8/CSC/BLOCD8</td>
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<td>
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</td>
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<td>
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</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>RR-CirKits TC-64, TC-MkII</td>
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<td>
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</td>
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<td>Required for power **</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
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<td>RR-CirKits LNCP</td>
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<td>
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</td>
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<td>
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</td>
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<td>Required</td>
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<td>
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</td>
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</tr>
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<tr class="ctr">
|
|
<td>RR-CirKits Motorman, MotorMan-II,<br>SignalMan, TowerMan, Watchman</td>
|
|
<td>
|
|
</td>
|
|
<td>
|
|
</td>
|
|
<td>Required</td>
|
|
<td>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr class="ctr">
|
|
<td>RR-CirKits LocoNet-Terminator</td>
|
|
<td>
|
|
</td>
|
|
<td>Can provide DC power</td>
|
|
<td>Can provide Termination</td>
|
|
<td>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr class="ctr">
|
|
<td>RR-CirKits SSB-Gateway</td>
|
|
<td>
|
|
</td>
|
|
<td>Can provide DC power</td>
|
|
<td>Can provide Termination</td>
|
|
<td>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr class="ctr">
|
|
<td>CML Electronics DAC10, DAC20</td>
|
|
<td>
|
|
</td>
|
|
<td>
|
|
</td>
|
|
<td>Required</td>
|
|
<td>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr class="ctr">
|
|
<td>CML Electronics SIGM10</td>
|
|
<td>
|
|
</td>
|
|
<td>?</td>
|
|
<td>Required</td>
|
|
<td>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr class="ctr">
|
|
<td>CML Electronics SIGM20, DTM30, TXC1</td>
|
|
<td>
|
|
</td>
|
|
<td>Requires DCC Signal</td>
|
|
<td>Required</td>
|
|
<td>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr class="ctr">
|
|
<td>CML Electronics LocoShuttle</td>
|
|
<td>Provides Slot Management</td>
|
|
<td>Generates RailSync</td>
|
|
<td>Required</td>
|
|
<td>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr class="ctr">
|
|
<td>Logic Rail Technologies LocoNet Fast Clock</td>
|
|
<td>
|
|
</td>
|
|
<td>
|
|
</td>
|
|
<td>Required</td>
|
|
<td>Required, can provide</td>
|
|
</tr>
|
|
|
|
<tr class="ctr">
|
|
<td>Tam Valley Depot Quad-LN, Quad-LN-S</td>
|
|
<td>
|
|
</td>
|
|
<td>
|
|
</td>
|
|
<td>Required</td>
|
|
<td>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr class="ctr">
|
|
<td>Möllehem Gårdsproduktion (MGP)<br>LocoNet Termination card</td>
|
|
<td>
|
|
</td>
|
|
<td>Can provide DC power</td>
|
|
<td>Can provide Termination</td>
|
|
<td>
|
|
</td>
|
|
</tr>
|
|
|
|
<tr class="ctr">
|
|
<td>N3IX RailSync Power and Termination Board</td>
|
|
<td>
|
|
</td>
|
|
<td>Can provide DC power</td>
|
|
<td>Can provide Termination</td>
|
|
<td>
|
|
</td>
|
|
</tr>
|
|
</table>
|
|
|
|
<p>Notes:</p>
|
|
|
|
<p>* Some circuitry may be required to generate the RailSync signals from a non-LocoNet
|
|
booster. See <a href="#rsfromnondtcs">RailSync from a non-Digitrax command station</a>,
|
|
below.</p>
|
|
|
|
<p>** LocoNet devices with an isolated LocoNet interfaces must take power from the
|
|
LocoNet RailSync wires to power the LocoNet side of their isolation hardware. These
|
|
devices may not require that the RailSync wires have a copy of the DCC track signal,
|
|
but they do require sufficient voltage and current. A DC power supply, as shown below
|
|
in <a href="#rspowersupply">RailSync power from a DC power supply</a>, is sufficient to
|
|
meet the power needs of the LocoBuffer-II, the LocoBuffer-USB, the LocoBuffer-USB
|
|
Rev-n, and the TC-64. If the RailSync wires do not provide sufficient voltage and
|
|
current, these devices will be unable to communicate reliably with LocoNet.</p>
|
|
|
|
<p>*** Some versions of the LocoBuffer design can provide LocoNet termination if
|
|
additional components are installed on the LocoBuffer board. Other versions of the
|
|
original LocoBuffer design do not have places for the additional components to be
|
|
installed. These comments do not apply to the LocoBuffer-II or LocoBuffer-USB
|
|
designs.</p>
|
|
|
|
<p>**** Intellibox documentation notes that only opto-isolated boosters may be
|
|
connected to its LocoNet connection. It is unclear whether any device using the signal
|
|
on the RailSync lines from the Intellibox must have opto-isolation circuitry.</p>
|
|
|
|
<p>***** PR4 devices require either a low-power copy of the DCC Track Signal or DC
|
|
power on the "RailSync" wires. The PR4 uses the signal on the RailSync wires to power
|
|
its LocoNet isolation and interface circuitry. Failure to provide sufficient power on
|
|
the RailSync wires will prevent the PR4 from communicating with LocoNet or result in
|
|
unreliable communication. The PR4 <em>cannot</em> provide LocoNet Data Signal
|
|
"Termination".</p>
|
|
|
|
<h3 id="dataterm">LocoNet Data Signal "Termination"</h3>
|
|
|
|
<p>"Termination" of the LocoNet Data Signal is something that allows the LocoNet data path to
|
|
work. One device on LocoNet must provide this "termination" so that all LocoNet devices may
|
|
communicate on the LocoNet "data" wires. Without this "termination", LocoNet devices cannot
|
|
pass LocoNet messages to each other.</p>
|
|
|
|
<p>LocoNet Data Signal "Termination" has been called many different things. Some alternate
|
|
terms are listed here. The BDL168 manual defines an OpSw setting which "Allows this BDL168
|
|
board to terminate LocoNet". The LocoBuffer-II and LocoBuffer-USB devices (except not the
|
|
LocoBuffer-USB Rev-n) have a hardware jumper which allows these devices to "provide LocoNet
|
|
Master termination". The PR3 has an operating mode where "The PR3 has the ability to act as a
|
|
LocoNet terminator." All of these are describing the term used in this document, LocoNet Data
|
|
Signal Termination.</p>
|
|
|
|
<h4 id="hwdataterm">Some commercial hardware which can provide LocoNet Data signal
|
|
termination</h4>
|
|
|
|
<ul>
|
|
<li>
|
|
<strong>BDL16, BDL162, BDL168</strong>
|
|
<p>The instructions in the BDL16x manual includes a section on how to use the BDL168x
|
|
with a non-Digitrax layout. This section mentions setting one of the BDL16x boards to act
|
|
as a LocoNet master by properly configuring a BDL16x OpSw. Doing this can set the BDL16x
|
|
board to provide LocoNet Data signal termination, and to act as a LocoNet Master.</p>
|
|
|
|
<p>The BDL16x board provides two ways to configure a BDL16x board to provide LocoNet Data
|
|
Signal Termination. One mechanism is only usable when the BDL16x is connected to a
|
|
LocoNet which has LocoNet Data Signal Termination from some other source, and requires
|
|
use of some other device to send LocoNet switch commands to the BDL16x. The other
|
|
mechanism does not require a functioning LocoNet.</p>
|
|
|
|
<ul>
|
|
<li>When using a functioning LocoNet to configure a BDL16x to provide LocoNet Data
|
|
Signal Termination, it is necessary to provide power to the BDL168 through its edge
|
|
connector, and to connect it to a functioning LocoNet. Then place the BDL16x into its
|
|
OpSw mode (see BDL16x documentation), and use a throttle or computer or other device to
|
|
send a switch command to "Close" OpSw 12. Then return the BDL16x to normal operating
|
|
mode (as described in the BDL16x documentation). If you will have multiple BDL16x
|
|
boards connected to your standalone LocoNet, or to avoid sensor address conflicts with
|
|
other devices which implement sensor messages, it is a good time to change the BDL16x
|
|
board's BDL168's Board Address (also called Board ID). Follow the instructions in the
|
|
BDL16x documentation for this.</li>
|
|
|
|
<li>If a functioning LocoNet is not available, use the "pushbutton" mechanism to
|
|
configure the BDL16x board for either "direct home" layout wiring or "common rail"
|
|
layout wiring, as described in BDL16x documentation. When this is done, the following
|
|
BDL16x OpSw values are forced:
|
|
<ul>
|
|
<li>BDL16x OpSw11 is forced to "c", which forces the BDL16x to act as a LocoNet
|
|
"master".</li>
|
|
|
|
<li>BDL16x OpSw12 is forced to "c", which forces the BDL16x to provide LocoNet Data
|
|
Signal Termination.</li>
|
|
|
|
<li>Depending on which button is used with this mechanism, BDL16x OpSw1 is forced
|
|
either to "t" for "direct home" layout wiring or to "c" for "common rail" layout
|
|
wiring.</li>
|
|
</ul>
|
|
</li>
|
|
</ul>
|
|
|
|
<p>Once you have established a functioning standalone LocoNet, additional BDL16x boards
|
|
can be added. Each should have its own Board ID (Board Address) number so that BDL16x
|
|
sensor numbers do not overlap sensor numbers for other boards or sensor numbers used by
|
|
other devices on the standalone LocoNet.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<p id="PR3config">The PR3 provides two different operating modes which may be useful when
|
|
the PR3 is used to interface to a standalone LocoNet. One useful mode provides <a href=
|
|
"#dataterm">LocoNet Data Signal "Termination"</a> in its MS100 mode, while the other
|
|
mode does not provide LocoNet Data Signal termination.</p>
|
|
|
|
<ul>
|
|
<li>
|
|
<p>For the case where the PR3 must provide <a href="#dataterm">LocoNet Data Signal
|
|
"Termination"</a>, and where the PR3 is connected to a suitable live power source via
|
|
its "Power" jack, JMRI should be configured in a way which will automatically set the
|
|
PR3 to its "MS100 mode with termination" mode at JMRI program start-up time. This can
|
|
be accomplished by configuring the JMRI connection settings for the PR3 so that the
|
|
"<code>Command Station type:</code>" is set to
|
|
<span class="wide">
|
|
"<code>Stand-alone LocoNet; interface device 'terminates' the LocoNet Data signal</code>"
|
|
</span>
|
|
(currently the Terminate option is not available)
|
|
</p>
|
|
|
|
<p>Note that this PR3 operating mode is not recommended when there is some other
|
|
source of "LocoNet Data Signal Termination" connected to LocoNet, and it is not
|
|
suitable when the PR3 is not provided suitable power via its "Power" barrel jack.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<p>If, instead, the PR3 will be connected to a LocoNet where some other device
|
|
provides <a href="#dataterm">LocoNet Data Signal "Termination"</a>, then it is more
|
|
appropriate to use the PR3 in its MS100 mode <em>without</em> enabling the PR3's Data
|
|
signal termination feature. In this case, it is appropriate to configure the PR3
|
|
connection for a "<code>Command Station type:</code>" of
|
|
<span class="wide">
|
|
"<code>Stand-alone LocoNet; interface device does not 'terminate' the LocoNet
|
|
Data signal</code>"
|
|
</span>
|
|
(currently the Terminate option is not available)
|
|
</p>
|
|
</li>
|
|
</ul>
|
|
</li>
|
|
|
|
<li>
|
|
<strong>LocoBuffer-II, LocoBuffer-USB (revisions before Rev N)</strong>
|
|
<p>See the instructions for the appropriate hardware for the required switch and/or
|
|
jumper settings. These devices power their LocoNet data signal termination using power
|
|
provided by the LocoNet RailSync wires.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<strong>LocoBuffer</strong>
|
|
<p>Some versions of the original LocoBuffer design allow the builder to add components to
|
|
provide LocoNet Data signal termination. Consult your LocoBuffer documentation to
|
|
determine whether your hardware can provide LocoNet Data signal termination.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<strong>RR-CirKits LocoNet-Terminator</strong>
|
|
<p>This device may be configured to provide LocoNet Data Signal termination. It may also
|
|
be configured to provide DC power on the RailSync wires.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<strong>RR-CirKits SSB-Gateway</strong>
|
|
<p>This device may be configured to provide LocoNet Data Signal termination. It may also
|
|
be configured to provide DC power on the RailSync wires.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<strong>Möllehem Gårdsproduktion LocoNet Termination card</strong>
|
|
<p>This device may be configured to provide LocoNet Data Signal termination. It may also
|
|
be configured to provide DC power on the RailSync wires.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<strong>N3IX RailSync Power and Termination Board</strong>
|
|
<p>This device may be configured to provide LocoNet Data Signal termination. It may also
|
|
be configured to provide external DC power on the RailSync wires for both of its LocoNet
|
|
connectors. Alternatively, it may be configured to provide external DC power only to
|
|
one of the two LocoNet ports, allowing the device to provide an external power source in
|
|
cases where there is too much RailSync loading on a portion of the LocoNet and where
|
|
portion does not need an active RailSync signal.</p>
|
|
</li>
|
|
|
|
</ul>
|
|
|
|
<h4 id="diyhwdataterm">Do-it-yourself LocoNet Data Signal Termination</h4>
|
|
|
|
<p>LocoNet cannot operate without "LocoNet Data Signal termination". When using a PR4, a
|
|
LocoBuffer-USB Rev N, a LocoBuffer-USB Rev O, or other LocoNet interface device which cannot
|
|
provide LocoNet Data Signal termination, you must provide some other device which can provide
|
|
that termination. Several common LocoNet devices are able to provide this function, as shown
|
|
in the table at the beginning of this page. If you are not using any LocoNet device which can
|
|
provide that termination, you will need to provide it as a do-it- yourself project. Such a
|
|
do-it-yourself LocoNet Data Signal Termination will typically be implemented in a way that is
|
|
similar to the diagram here:</p>
|
|
<img src="images/LocoNetDataSignalTermination.png" alt=
|
|
"Image showing general LocoNet Data Signal Termination Diagram">
|
|
<p>The 15 mA current source block in the diagram above may be implemented in a wide variety
|
|
of ways. As an example, Dick Bronson shows a circuit for a 15 mA current source that can be
|
|
used to provide LocoNet Data Signal termination at his <a href=
|
|
"http://www.rr-cirkits.com">RR-CirKits website</a> on the <a href=
|
|
"http://www.rr-cirkits.com/Notebook/Standalone-LocoNet.html">Notebook page for Standalone
|
|
LocoNet</a>. Look for the section titled "Pull Up" which shows a circuit using two 2N2222 NPN
|
|
transistors and two resistors. The circuit node shown as <strong>LN</strong> should be
|
|
connected to the LocoNet "Data" pins - pins 3 and 4 (typically the red and green wires), as
|
|
is shown in the diagram above for the "Out" connection of the current source.</p>
|
|
|
|
<p>Dick's circuit should be powered by a 12VDC regulated power supply capable of providing at
|
|
least 15mA. The power supply negative terminal should be connected to the LocoNet "Ground"
|
|
pins - pins 2 and 5 (typically the yellow and black wires). This power supply can be used to
|
|
power other devices so long as they either have <strong>no</strong> electrical path back to
|
|
any LocoNet wire, or so long as they connect the power supply negative terminal directly to
|
|
the LocoNet "Ground" pins.</p>
|
|
|
|
<p>Other Internet resources may show circuits for LocoNet termination.</p>
|
|
|
|
<h4 id="datatermech">Technical information about LocoNet Data Signal "Termination"</h4>
|
|
|
|
<p>Technically, the term "termination" can be somewhat misleading. For our purposes, LocoNet
|
|
data signal "termination" is a current source which provides a positive 15 mA current source
|
|
from a +12V supply, and which is connected to the LocoNet "Data" pins (pins 3 and 4), and
|
|
which is referenced to the LocoNet "Ground" pins (pins 2 and 5). This provides a "pull-up"
|
|
for the "wired-or" signaling used on the LocoNet "data" wires.</p>
|
|
|
|
<p>Some Digitrax documentation describes devices which can act as the LocoNet "master", and
|
|
other Digitrax documentation describe the "LocoNet Master" as (in part) the LocoNet device
|
|
which provides the current source for the LocoNet data lines. So, the term "LocoNet Master"
|
|
may sometimes imply a device which can provide the LocoNet Data signal termination.</p>
|
|
|
|
<p>In this context, "data signal termination" does <strong>not</strong> refer to "electrical
|
|
transmission line termination". According to Digitrax documentation, there should not be any
|
|
need to provide "electrical transmission line termination" on the LocoNet data signal.</p>
|
|
|
|
<h3 id="railsyncgen">LocoNet RailSync Signal "Generation"</h3>
|
|
|
|
<p>As shown in the table above, some LocoNet devices require that the RailSync wires on the
|
|
LocoNet cable are powered or are an accurate representation of the DCC track signal. In cases
|
|
where the standalone LocoNet needs only to provide power to LocoNet devices on the standalone
|
|
LocoNet, a simple power supply which provides about 1 Amp at 12VDC is sufficient. In other
|
|
cases, one or more LocoNet device requires an accurate representation of the DCC track signal
|
|
on the standalone LocoNet cable.</p>
|
|
|
|
<h4 id="hwdctorailsync">Some commercial hardware which can provide DC power to the LocoNet
|
|
RailSync wires</h4>
|
|
|
|
<ul>
|
|
<li>
|
|
<strong>RR-CirKits LocoNet-Terminator</strong>
|
|
<p>This device may be configured to provide DC power on the RailSync wires. It may also
|
|
be configured to provide LocoNet Data Signal termination.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<strong>RR-CirKits SSB-Gateway</strong>
|
|
<p>This device may be configured to provide DC power on the RailSync wires. It may also
|
|
be configured to provide LocoNet Data Signal termination.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<strong>Möllehem Gårdsproduktion LocoNet Termination card</strong>
|
|
<p>This device may be configured to provide DC power on the RailSync wires. It may also
|
|
be configured to provide LocoNet Data Signal termination.</p>
|
|
</li>
|
|
|
|
<li>
|
|
<strong>N3IX RailSync Power and Termination Board</strong>
|
|
<p>Among other options, this device may be configured to provide DC power on the
|
|
RailSync wires. It may also be configured to provide LocoNet Data Signal termination.</p>
|
|
|
|
</ul>
|
|
|
|
<h4 id="rspowersupply">RailSync power from a DC power supply</h4>
|
|
|
|
<p>For cases where the standalone LocoNet does need to provide power to the RailSync lines
|
|
but does <strong>not</strong> need to provide a low-power version of the DCC track signal, a
|
|
simple power supply connected to the LocoNet RailSync and "Ground" wires is sufficient. The
|
|
diagram below shows such a circuit.</p>
|
|
<img src="images/SimpleRailSyncPowerSupply.png" alt=
|
|
"Image showing a circuit for simple power supply for RailSync+/-">
|
|
<p>Notes:</p>
|
|
|
|
<ul>
|
|
<li>The power supply shown above must not be used to provide power to any other devices
|
|
except via the standalone LocoNet RailSync wires. This restriction prevents the possibility
|
|
of unintended current paths which could cause damage to the power supply, LocoNet wiring,
|
|
or the other device(s) on LocoNet.</li>
|
|
|
|
<li>This circuit must not be used in conjunction with any other device or circuit which
|
|
actively puts a signal on the standalone LocoNet RailSync wires.</li>
|
|
</ul>
|
|
|
|
<h4 id="rsfromdtcs">RailSync from a Digitrax command station</h4>
|
|
|
|
<p>If the Digitrax command station's LocoNet "Ground" wire can be safely connected directly
|
|
to the standalone LocoNet "Ground" wire, it is sufficient to connect the Digitrax Command
|
|
Station RailSync+, RailSync-, and "Ground" wires to the comparable wires on the standalone
|
|
LocoNet.</p>
|
|
|
|
<p>Do <strong>not</strong> make any connections between the standalone LocoNet's red or green
|
|
wires and <strong>any</strong> wire on the command station's LocoNet. Doing so would make the
|
|
standalone LocoNet just another part of the primary LocoNet.</p>
|
|
<img src="images/RailSyncFromPrimaryLocoNet.jpg" alt=
|
|
"Image showing creation of Standalone LocoNet RailSync from primary LocoNet">
|
|
<p>Note that this circuit must not be used in conjunction with any other device or circuit
|
|
which actively puts a signal on the standalone LocoNet RailSync wires.</p>
|
|
|
|
<p>If there is any concern about sneak paths between the power supply for the Digitrax
|
|
command station and the standalone LocoNet, then some sort of isolation <strong>must</strong>
|
|
be provided. Isolation of this nature is beyond the scope of this documentation;
|
|
opto-isolators could be used for this purpose.</p>
|
|
|
|
<h4 id="rsfromnondtcs">RailSync from a non-Digitrax command station</h4>
|
|
|
|
<p>The Digitrax BDL16x manual gives recommendations for providing a "RailSync+" signal from
|
|
the "Rail A" output of a non-Digitrax DCC booster. This instruction assumes that you have or
|
|
will implement the wiring shown for "direct home wiring" or "whole layout common rail wiring"
|
|
as shown in a previous diagram. The important points to remember are that the BDL16x board
|
|
requires that it receive the "Rail A" signal on its RailSync+ input (on the LocoNet jack),
|
|
that the BDL16x be wired in series on the "Rail A" side of the track connection,
|
|
<strong>and</strong> that there is a "booster ground" connection to the BDL16x board pin 11.
|
|
If the "booster ground" connection is not made, the BDL16x detection will not work
|
|
properly.</p>
|
|
|
|
<p>Additionally, it may be advisable to provide some current limiting device, such as a
|
|
series resistor, between the booster Rail A connection the RailSync+ wire on the standalone
|
|
LocoNet.</p>
|
|
|
|
<p>While this may be suitable for BDL168 operation, other LocoNet devices may require both a
|
|
RailSync+ and RailSync- signal. In this case, connections from Rail A to RailSync+, and from
|
|
Rail B to RailSync- may be appropriate. Again, current limiting resistors may be
|
|
advisable.</p>
|
|
|
|
<p>Note that this type of circuit must not be used in conjunction with any other device or
|
|
circuit which actively puts a signal on the standalone LocoNet RailSync wires.</p>
|
|
|
|
<p>To avoid the possibility of "sneak paths" between the non-Digitrax booster and the
|
|
stand-alone LocoNet, opto-isolation may be advisable. For "common rail" wiring,
|
|
opto-isolation is required, as shown in the BDL168 manual diagram showing "common rail
|
|
wiring". Some booster manufacturers only offer opto-isolated boosters, and some other booster
|
|
manufacturers offer some models which include optical isolation.</p>
|
|
|
|
<h5 id="rsfromncecs">RailSync from an NCE command station</h5>
|
|
|
|
<p>NCE has recommended at least two different ways to use NCE Control Bus signals to create
|
|
RailSync+ and RailSync- for use by Digitrax Boosters. The diagram below, based on one shown
|
|
in an NCE document, shows what is believed to be a good way to do this.</p>
|
|
<img src="images/RailSyncFromNCEControlBus.png" alt=
|
|
"Image showing circuit to create Standalone LocoNet RailSync from NCE Control Bus Control+/-">
|
|
<p>Notes:</p>
|
|
|
|
<ul>
|
|
<li>These types of circuits must not be used in conjunction with any other device or
|
|
circuit which actively puts a signal on the standalone LocoNet RailSync wires.</li>
|
|
|
|
<li>Another NCE document shows a diagram without any resistors, and with the relationship
|
|
between NCE Control+/- and RailSync+/- wires swapped, but it does not mention any
|
|
connection to the LocoNet black wire. It is believed that such a circuit might work but
|
|
would be more sensitive to electrical noise than the circuit shown above.</li>
|
|
</ul>
|
|
|
|
<h3 id="pseudoground">BDL16x connection to a DCC system without a "Ground" terminal</h3>
|
|
|
|
<p>According to BDL16x documentation, proper BDL16x operation <strong>requires</strong> a
|
|
"ground" connection to the DCC booster, via pin 11 on the BDL16x connector. But some boosters
|
|
do not have any documented "ground" connection.</p>
|
|
|
|
<p>The following circuit has been used to allow connection of a BDL16x for occupancy
|
|
detection with the Hornby Elite DCC system, which does not have a "ground" connection. This
|
|
circuit creates a "pseudo-ground" from the DCC track signal which can be used as the "Ground"
|
|
for the connection to the BDL16x.</p>
|
|
<img src="images/PseudoGroundForBdl16x.jpg" alt=
|
|
"Image showing circuit to generate a pseudo-ground from a command station without a 'ground' connection">
|
|
<p>Note that this "pseudo-ground" should only be connected to BDL16x devices.</p>
|
|
|
|
<h3 id="multipleconnections">Multiple active LocoNet connections</h3>
|
|
|
|
<p>When a JMRI profile is configured for more than one active LocoNet connection, JMRI treats
|
|
each active LocoNet connection as if it is connected to an independent LocoNet. When JMRI
|
|
sends a message to LocoNet, it will send only to one of those LocoNet connections, depending
|
|
on how that LocoNet traffic is generated within JMRI.</p>
|
|
|
|
<h4 id="routeconnprefix">Routing LocoNet messages to a LocoNet connection based on
|
|
"Connection Prefix"</h4>
|
|
|
|
<p>Each active LocoNet connection within a given JMRI profile has a unique "Connection
|
|
Prefix" as well as a unique "Connection Name". For each active LocoNet connection, the main
|
|
window of the JMRI tool will show one pull-down menu for each active LocoNet connection,
|
|
where each pull-down menu item, and each is named for the "Connection Name" assigned in the
|
|
connection.</p>
|
|
|
|
<p>When using a tool from a given LocoNet pull-down menu, the tool will direct its LocoNet
|
|
messages to the hardware interface associated with the "Connection Name" shown as the
|
|
pull-down menu name.</p>
|
|
|
|
<p>For example, consider a JMRI profile with three active LocoNet connections, named
|
|
"LocoNet", "LocoNet2", and "LocoNet3". If one opens up the "Configure Command Station" tool
|
|
in the "LocoNet2" menu, the LocoNet messages related to that tool window will be sent to and
|
|
received from the hardware connection which is configured with the connection name
|
|
"LocoNet2". The tool will not send its messages to the hardware connections related to the
|
|
connections with Connection Names "LocoNet" and "LocoNet3", and the tool will not pay
|
|
attention to traffic received by JMRI via the hardware connections associated with the
|
|
"LocoNet" and "LocoNet3" connections.</p>
|
|
|
|
<h4 id="routeConName">Routing LocoNet messages to a LocoNet connection based on "Connection
|
|
Name"</h4>
|
|
|
|
<p>Similarly, when JMRI works with a resource that is defined using a "Connection Prefix", it
|
|
will work with the hardware connection associated with that "Connection Prefix", and it will
|
|
not attempt to work with a resource which has the same resource number but with a different
|
|
"Connection Prefix".</p>
|
|
|
|
<p>As an example, if JMRI attempts to control L3T45, it will send its turnout control message
|
|
to the hardware interface associated with the connection prefix "L3", but will not send
|
|
control messages to the hardware associated with connection prefix "L" or to the hardware
|
|
associated with connection prefix "L2". Similarly, messages on the hardware connection
|
|
associated with connection prefix L3 will have an effect on JMRI's interpretation of the
|
|
state of L3S512, while LocoNet messages on the hardware connections associated with
|
|
connection prefix L and connection prefix L2 will not affect JMRI's interpretation of the
|
|
state of L3S512.</p>
|
|
|
|
<h4 id="routedefault">Routing LocoNet messages to a LocoNet connection based on "Default"
|
|
settings</h4>
|
|
|
|
<p>JMRI allows the user to to configure how some of the JMRI tools route their messages to
|
|
the various connections by default. This configuration is done via the profile's
|
|
"Preferences", in the "Defaults" configuration tab. These settings force the JMRI tools to
|
|
<strong>assume</strong> that certain operations will be directed to certain hardware
|
|
connections, unless the tool allows a specific interface to be selected using a "Connection
|
|
Prefix" or some other tool-specific mechanism.</p>
|
|
|
|
<p>For example, some JMRI users will have a PR3/PR4 connection for mobile decoder
|
|
programming, and another LocoNet connection for communicating with the command station,
|
|
turnouts, throttles, etc. In this case, the "Defaults" settings would configure the hardware
|
|
connection associated with the PR3/PR4 programming track as the "Programmer" connection,
|
|
while the other LocoNet connection would be configured as the communications path for
|
|
"Throttles", "Power Control", and "Command Station".</p>
|
|
|
|
<h4 id="multconsingle">Multiple active LocoNet connections to a single LocoNet</h4>
|
|
|
|
<p>JMRI is designed upon the assumption that each of JMRI's LocoNet hardware connections are
|
|
connected to <strong>independent</strong> LocoNet busses. If the user has connected the
|
|
LocoNet cabling so that more than one JMRI LocoNet hardware interface connects to the same
|
|
LocoNet, then LocoNet traffic seen on one connection will be seen on the other connected
|
|
LocoNet hardware connection(s).</p>
|
|
|
|
<p>As an example of this, consider a JMRI profile which configures three active LocoNet
|
|
connections, with connection names "LocoNet", "LocoNet2", and "LocoNet3". Assume that the
|
|
first and second of these are connected to the same LocoNet, while "LocoNet3" is connected to
|
|
an independent LocoNet. If JMRI sends a Switch control message to LT604, JMRI will "see" that
|
|
switch control message as a change to L2T604 when the second LocoNet hardware interface sees
|
|
the message sent by the first LocoNet hardware interface. But L3T604 will not be changed,
|
|
because LocoNet3 is an independent LocoNet implementation in this example, so it would not
|
|
see the traffic generated by JMRI when controlling LT604.</p>
|
|
|
|
<p>Note that this type of connectivity can cause difficulty with the JMRI turnout retry
|
|
mechanism for any active LocoNet which is connected to a LocoNet-based command station, as
|
|
described in <a href="Digitrax.shtml#TurnoutCmdHandling">Command Station Turnout Command
|
|
Rejection and JMRI Turnout Command Handling</a>.</p>
|
|
|
|
<h3 id="sneakpaths">"Sneak paths" and Computer Interfaces</h3>
|
|
|
|
<p>When multiple devices share different types of electrical connections, unexpected current
|
|
paths can be present that can cause malfunction or component failure. A properly designed and
|
|
implemented system prevents these problems.</p>
|
|
|
|
<p>A good example of this type of problem is the connectivity that begins at the (power
|
|
receptacle) wall outlet, through power supplies, boards, interface devices and computers. If
|
|
there is "electrical connectivity" between the wall outlet and the output of a power supply,
|
|
and the power supply is electrically connected to a board such as a BDL16x, and the board is
|
|
electrically connected to a LocoNet bus, and the LocoNet bus is electrically connected to a
|
|
computer interface, and the computer interface is connected to a personal computer, and the
|
|
personal computer is connected to a power supply, and the power supply is connected to the
|
|
wall outlet, there could be a "sneak path" for electrical current around the electrical
|
|
connectivity loop. If the electrical current happens to exceed the ratings of any component
|
|
in the loop, there can be a failure of that component, and perhaps components to which it is
|
|
connected.</p>
|
|
|
|
<p>How can such a problem be avoided? By careful planning of the electrical connectivity
|
|
within a system, and inclusion of some form of "isolation" where electrical connectivity
|
|
concerns arise. It is usually very difficult to determine the electrical connectivity within
|
|
a computer power supply, so it is generally a good idea to isolate the computer from the
|
|
remainder of the system.</p>
|
|
|
|
<p>Isolation of LocoNet from the computer is recommended. The LocoBuffer-II, LocoBuffer-USB,
|
|
LocoBuffer-USB Rev-n and LocoBuffer-NG, and the Digitrax PR4 computer interface devices
|
|
provide "optical isolation" of the
|
|
LocoNet signals from the computer electrical signals. Note that the LocoBuffer-II isolation
|
|
is not effective when it is configured for "Local Power". The LocoBuffer-II should be
|
|
configured for "isolated power" and should have an external power supply plugged in for
|
|
proper operation and isolation.</p>
|
|
|
|
<p>Other computer interfaces can be isolated using 3rd-party isolation devices. Placing a USB
|
|
hub with optical isolation between the computer and the USB device, or an RS232 optical
|
|
isolation device between the computer and the RS232-based interface device might provide a
|
|
safe and functional solution. Note, though, that some users have reported issues when using a
|
|
USB hub (whether optically isolated or not) with the PR3/PR4.</p>
|
|
|
|
<p>Similar "sneak path" problems can happen when sharing a single power supply for multiple
|
|
device types that share other connectivity. A LocoNet cable can provide that "other
|
|
connectivity", so devices which connect to LocoNet must be powered with care. A safe "general
|
|
rule" is that a power supply should be connected to, at most, one type of board.</p>
|
|
|
|
<h2 id="examples">Standalone LocoNet® Examples</h2>
|
|
|
|
<h3 id="isolthrdetsig">Isolating the LocoNet throttle bus from LocoNet Turnouts, Detection &
|
|
Signaling</h3>
|
|
|
|
<p>The diagram below shows an example with a LocoNet-based command station and throttles on a
|
|
"primary" LocoNet, and a standalone LocoNet which provides block detection, signal control,
|
|
and control of switches. In this example, devices on the "primary" LocoNet, including
|
|
throttles, cannot directly control switches or signals on the standalone LocoNet.</p>
|
|
|
|
<p><img src="images/ThrottleLocoNetIsolatedFromStandaloneLocoNet.jpg" alt=
|
|
"Image showing example of throttle LocoNet isolated from Standalone LocoNet">
|
|
</p>
|
|
|
|
<p>JMRI signal control logic can interpret the LocoNet block occupancy report messages
|
|
generated by the BDL168s, and can control signal aspects by generating appropriate LocoNet
|
|
messages to the SE8Cs. JMRI can also control switches connected to the DS64. This type of
|
|
connectivity may be useful when JMRI is used to implement a CTC panel.</p>
|
|
|
|
<p>For the connectivity shown in this diagram, the standalone LocoNet data wires are not
|
|
connected to the primary LocoNet, so LocoNet Master termination cannot be provided by the
|
|
command station. An alternative source of LocoNet Data Signal Termination must be used. The
|
|
LocoBuffer-USB (except not LocoBuffer-USB Rev-n) can easily be configured to provide "LocoNet
|
|
Master termination" via an internal jumper setting (see the LocoBuffer-USB User's Manual).
|
|
Alternate sources of <a href="#dataterm">LocoNet Data Signal Termination</a> are described
|
|
above.</p>
|
|
|
|
<p>With the connectivity shown in the diagram above, the DS64 does not get its switch
|
|
commands from DCC track power. This is an intentional choice. Connecting DS64s so that they
|
|
do not get track power can help avoid some DS64 instability which has been reported by some
|
|
users. Instead, the DS64 gets its power from an external power supply, and gets its switch
|
|
control commands from LocoNet.</p>
|
|
|
|
<p>This diagram assumes that there are no sneak current paths between any device associated
|
|
with the standalone LocoNet and any device associated with the primary LocoNet. This allows
|
|
connection of the Digitrax command station's LocoNet "Ground" wire to the standalone LocoNet
|
|
"Ground" wire. It also shows the use of two LocoBuffer-USB devices as computer interfaces.
|
|
These devices provide optical isolation of the signaling between the "computer" side of the
|
|
device and the "LocoNet" side of the device, which eliminates "sneak current paths" between
|
|
each LocoNet and the computer. If one or more LocoNet interface device is used which does
|
|
<strong>not</strong> provide isolation, then there is a possibility that "sneak current
|
|
paths" could be present. See <a href="#sneakpaths">"Sneak paths" and Computer Interfaces</a>,
|
|
above, for more information.</p>
|
|
|
|
<h3 id="bdl168wnondtcs">Switches (DS64), Detection (BDL168) and Signals (SE8C) with
|
|
non-Digitrax DCC command station</h3>
|
|
|
|
<p>The diagram below shows a possible implementation of a standalone LocoNet for
|
|
computer-controlled signaling using Digitrax BDL168 boards for occupancy detection, Digitrax
|
|
SE8C boards for driving signals, and Digitrax DS64s for controlling switches. For this
|
|
example, one of the BDL168 boards should be configured to provide LocoNet data signal
|
|
termination.</p>
|
|
<img src="images/SwitchesAndDetectionAndSignallingExample.jpg" alt=
|
|
"Image showing Standalone LocoNet for DS64, SE8C, BDL168 when using a non-Digitrax Command Station">
|
|
<p>JMRI signal control logic can interpret the LocoNet block occupancy report messages
|
|
generated by the BDL168s, and can control signal aspects by generating appropriate LocoNet
|
|
messages to the SE8Cs. JMRI can also control switches connected to the DS64. This type of
|
|
connectivity may be useful when JMRI is used to implement a CTC panel.</p>
|
|
|
|
<p>The RailSync Generator block should be implemented as described in <a href=
|
|
"#rsfromnondtcs">RailSync from a non-Digitrax command station</a>.</p>
|
|
|
|
<p>For the connectivity shown in this diagram, the DS64 should be configured to take its
|
|
switch control messages from LocoNet instead of from its DCC track inputs. This should avoid
|
|
some reported instability of DS64s when connected to the DCC track signal.</p>
|
|
|
|
<p>This diagram assumes that an isolated computer interface is used to prevent "sneak current
|
|
paths" between the standalone LocoNet and the computer. If one or more LocoNet interface
|
|
device is used which does <strong>not</strong> provide isolation, then there is a possibility
|
|
that "sneak current paths" could be present. See <a href="#sneakpaths">"Sneak paths" and
|
|
Computer Interfaces</a>, above, for more information.</p>
|
|
|
|
<h3 id="se8csigwodtcs">SE8C signaling without a Digitrax command station</h3>
|
|
|
|
<p>The diagram below shows a possible implementation of a standalone LocoNet for
|
|
computer-controlled signaling using Digitrax SE8C boards. The example assumes that any
|
|
detection information on the standalone LocoNet is not gathered from a device connected to
|
|
the standalone LocoNet which would require a copy of the DCC track signal on the standalone
|
|
LocoNet RailSync+/- wires. Because this standalone LocoNet does not require active
|
|
RailSync+/- signals, there is no need for a connection to the booster track outputs. But the
|
|
LocoBuffer-USB requires RailSync power when it is in its LocoNet termination mode, so a
|
|
RailSync power supply is shown.</p>
|
|
|
|
<p>The RailSync power could be supplied by a do-it-yourself supply as described in <a href=
|
|
"#rspowersupply">RailSync power from a DC power supply</a> above, or via a commercial device
|
|
which can supply DC power to the standalone LocoNet RailSync wires, such as the RR-CirKits
|
|
LocoNet-Terminator or SSB-Gateway products.</p>
|
|
<img src="images/StandaloneLocoNetSignallingNet.jpg" alt=
|
|
"Image showing a Standalone LocoNet for SE8C signalling only">
|
|
<h2 id="acknowledgments">Acknowledgments</h2>
|
|
|
|
<p>Among others, Elmer McKay and Dick Bronson have provided significant input to the content
|
|
of this page. Thank you!</p>
|
|
<a id="tools"></a>
|
|
<h2 id="references">Documentation</h2>
|
|
|
|
<h3>Third Party info</h3>
|
|
|
|
<p>Information and support for Digitrax products may be found at <a href=
|
|
"https://www.digitrax.com">the Digitrax website</a>.</p>
|
|
|
|
<p>Information and support for the LocoBuffer-II, the LocoBuffer-USB, the LocoBuffer-USB
|
|
Rev-N and Rev-O, the LocoBuffer-NG, the LocoNet-Terminator, the SSB-Gateway, and other
|
|
products by RR-CirKits may be found at <a href="http://www.rr-cirkits.com/">the RR-CirKits
|
|
website</a>.</p>
|
|
|
|
<p>Information and support for products from Team Digital may be found at <a href=
|
|
"http://www.teamdigital1.com/">the Team Digital website</a>.</p>
|
|
|
|
<p>Information and support for the Logic Rail Technologies LocoNet Fast Clock may be found at
|
|
<a href="http://www.logicrailtech.com">the Logic Rail Technologies website</a>.</p>
|
|
|
|
<p>Information and support for products by CML Electronics is now provided by Sig-naTrak® by
|
|
GFB Designs at <a href="https://www.signatrak.co.uk/">the Sig-naTrak® website</a>.</p>
|
|
|
|
<p>Information and support for products by Tam Valley Depot may be found at <a href=
|
|
"http://www.tamvalleydepot.com/">the TAM Valley Depot website</a>.</p>
|
|
|
|
<p>Information and support for products by Möllehem Gårdsproduktion MGP) may be found at
|
|
<a href="http://www.mollehem.se/index.php/en/">The Möllehem Gårdsproduktion website</a>.</p>
|
|
|
|
<p>Information and support for products by N3IX) may be found at
|
|
<a href="https://quadln.n3ix.com/">The N3IX Engineering website</a>.</p>
|
|
|
|
<p>LocoNet® is a registered trademark of <a href="https://www.digitrax.com">Digitrax,
|
|
Inc.</a></p>
|
|
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