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<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html >
<head><title></title>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<meta name="generator" content="TeX4ht (http://www.tug.org/tex4ht/)">
<meta name="originator" content="TeX4ht (http://www.tug.org/tex4ht/)">
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</head><body
>
<!--l. 18--><p class="noindent" >
<!--l. 18--><p class="noindent" ><span
class="ecsx-1728">Interlocking</span>
<span
class="ecsx-1728">System</span>
<span
class="ecsx-1728">Guide</span>
<div class="tabular"> <table id="TBL-1" class="tabular"
cellspacing="0" cellpadding="0"
><colgroup id="TBL-1-1g"><col
id="TBL-1-1"></colgroup><tr
style="vertical-align:baseline;" id="TBL-1-1-"><td style="white-space:nowrap; text-align:left;" id="TBL-1-1-1"
class="td00"></td></tr></table>
</div>
<a
id="x1-2r1"></a>
<!--l. 20--><p class="noindent" ><span
class="ecsx-1200">1</span> <span
class="ecsx-1200">Introduction</span>
<a
id="Q1-1-0"></a>
<!--l. 22--><p class="noindent" >In real-world railways, a so-called interlocking system is a set of railway signals and trackside equipment. Its purpose is to prevent
conflicting train movements which otherwise could result in derailing or colliding trains. If you want more information, just search for
“railway interlocking” on the internet.
<!--l. 28--><p class="noindent" >Real-world interlocking systems perform this task by setting routes. A route is a path along a track that a train can safely pass. To set a
route for a train, the signalman (the operator of a signal box) has to set switches (turnouts) to the correct position and lock them in order
to make a signal for a train show “Proceed”. In newer systems, this is done automatically by the interlocking system. A route can
not be set if switches are locked to a wrong position by another route or if any portion of the route is occupied by a
train.
<!--l. 37--><p class="noindent" >The interlocking system in this Minetest mod tries to follow real-world interlocking systems as far as applicable. It divides tracks into
track sections and implements a route setting mechanism following the same principle.
<!--l. 42--><p class="noindent" >However, for the sake of simplicity of implementation and usage, not all concepts of real-world interlocking have been taken over.
Especially, there is no mechanism for overlap.
<!--l. 46--><p class="noindent" >If you are looking for a place to learn how real-world interlocking systems work, have a look at “SimSig”. By looking at their simulations,
you can obtain experience on how to set up your own interlocking systems in AdvTrains. The SimSig glossary is a good place to look up
unknown terms in this document.
<!--l. 52--><p class="noindent" >
<a
id="x1-3r2"></a>
<!--l. 52--><p class="noindent" ><span
class="ecsx-1200">2</span> <span
class="ecsx-1200">Setting</span>
<span
class="ecsx-1200">up</span>
<span
class="ecsx-1200">track</span>
<span
class="ecsx-1200">sections</span>
<a
id="Q1-1-0"></a>
<!--l. 54--><p class="noindent" >In the real world, a line of track is divided into so-called track sections, or track circuits. Those systems often can not tell
where exactly a train is, but only which track sections it occupies. A route can never be set through an occupied track
section.
<!--l. 59--><p class="noindent" >A track section often covers:
<ul class="itemize1">
<li class="itemize">A section on a main running line, between two signals
</li>
<li class="itemize">A single turnout
</li>
<li class="itemize">A rail crossing, or a set of turnouts acting as a double/single slip switch
</li>
<li class="itemize">A siding</li></ul>
<!--l. 67--><p class="noindent" >You will find some examples on how to interlock certain patterns later.
<!--l. 69--><p class="noindent" >
<a
id="x1-4r1"></a>
<!--l. 69--><p class="noindent" ><span
class="ecsx-1200">2.1</span> <span
class="ecsx-1200">Track</span>
<span
class="ecsx-1200">Circuit</span>
<span
class="ecsx-1200">Breaks</span>
<a
id="Q1-1-0"></a>
<!--l. 71--><p class="noindent" >In this mod, you will not directly configure the locations of track sections. Instead, you designate the borders of each track section using a
special node, the Track Circuit Break, abbreviated TCB.
<!--l. 75--><p class="noindent" >For example, if you want to create a track section for a piece of a main running line, you set up two TCBs at the ends of this track
circuit.
<!--l. 79--><p class="noindent" >Setting up a TCB works as follows:
<ol class="enumerate1" >
<li
class="enumerate" id="x1-6x1">Place a TCB node somewhere near the place where the circuit break is going to be located.
</li>
<li
class="enumerate" id="x1-8x2">Right-click the TCB node
</li>
<li
class="enumerate" id="x1-10x3">Punch the rail which should act as TCB</li></ol>
<!--l. 86--><p class="noindent" >The result should look like this:
<!--l. 88--><p class="noindent" ><img
src="0_home_moritz_Home_Projekte_Minetest_minetest_m___s_assets_lyx_img_screenshot_20180830_142551.png" alt="PIC"
>
<!--l. 90--><p class="noindent" >Now you have assigned the TCB node to a rail. Right-click the TCB node once again. This will bring up a form which looks as
follows:
<!--l. 93--><p class="noindent" ><img
src="1_home_moritz_Home_Projekte_Minetest_minetest_m____lyx_img_Bildschirmfoto_2018-08-30_14-26-35.png" alt="PIC"
>
<!--l. 95--><p class="noindent" >You see that the form is divided in side A and side B. To designate where each side is, a marker is displayed on the rail. You can always
make this marker show up by punching the TCB node, and remove it by punching the marker. Both sides are shown as “End of
interlocking”. This means that there is no track section set up at this place.
<!--l. 101--><p class="noindent" >You should repeat this procedure once again a few meters away from the first TCB to create a second TCB on the same
track.
<!--l. 104--><p class="noindent" ><img
src="2_home_moritz_Home_Projekte_Minetest_minetest_m____lyx_img_Bildschirmfoto_2018-08-30_14-32-48.png" alt="PIC"
>
<!--l. 106--><p class="noindent" >Once you have both bordering TCBs set up, you can now create the actual track section. To do this:
<ol class="enumerate1" >
<li
class="enumerate" id="x1-12x1">Right-click one of the TCBs
</li>
<li
class="enumerate" id="x1-14x2">Locate the correct side (A or B) to create the track section
</li>
<li
class="enumerate" id="x1-16x3">Click “Create interlocked Track Section” in the formspec on the chosen side.</li></ol>
<!--l. 114--><p class="noindent" >Now, the text on the formspec has changed. It shows something like this:
<!--l. 117--><p class="noindent" ><img
src="3_home_moritz_Home_Projekte_Minetest_minetest_m____lyx_img_Bildschirmfoto_2018-08-30_14-27-25.png" alt="PIC"
>
<!--l. 119--><p class="noindent" >Clicking “Show Track Section” brings up another formspec:
<!--l. 121--><p class="noindent" ><img
src="4_home_moritz_Home_Projekte_Minetest_minetest_m____lyx_img_Bildschirmfoto_2018-08-30_14-28-32.png" alt="PIC"
>
<!--l. 123--><p class="noindent" >On the top, you see a list of all TCBs that border this track section. In your case, there should be two TCBs listed. If there’s only one,
head over to <a
href="#x1-17r2">2.2<!--tex4ht:ref: subsec:Long-track-sections, --></a>. You should now select a name for the track section, to identify it later.
<!--l. 128--><p class="noindent" >The same procedure is applicable when you create a turnout track section, except that you have to set up three or more
TCBs.
<!--l. 131--><p class="noindent" >The AdvTrains interlocking system allows you to add more TCBs after you have created a track section. This works without problems in
most cases. For example, you can easily insert a turnout into an already set-up track section and create another TCB behind it, and
AdvTrains will automatically detect the existing track section. Problems arise only if you try to insert a TCB in-between a section, in
which case both sides of the TCB will end up assigned to the same section. The code currently does not handle this case properly, so try
to avoid this situation by all means. As a last resort, you can always dissolve a faulty track section, as described in the next
chapter.
<!--l. 142--><p class="noindent" >
<a
id="x1-17r2"></a>
<!--l. 142--><p class="noindent" ><span
class="ecsx-1200">2.2</span> <span
class="ecsx-1200">Long</span>
<span
class="ecsx-1200">track</span>
<span
class="ecsx-1200">sections,</span>
<span
class="ecsx-1200">crossings</span>
<span
class="ecsx-1200">and</span>
<span
class="ecsx-1200">other</span>
<span
class="ecsx-1200">edge</span>
<span
class="ecsx-1200">cases</span>
<a
id="Q1-1-0"></a>
<!--l. 144--><p class="noindent" >
<a
id="x1-18r1"></a>
<!--l. 144--><p class="noindent" ><span
class="ecsx-1000">2.2.1</span> <span
class="ecsx-1000">Very</span>
<span
class="ecsx-1000">long</span>
<span
class="ecsx-1000">track</span>
<span
class="ecsx-1000">sections</span>
<a
id="Q1-1-0"></a>
<!--l. 146--><p class="noindent" >If you try to set up a track section that is longer than 1000 nodes, advtrains won’t recognize the TCB at the other end because of a safety
limit in the traverser function, which is supposed to prevent deadlocks. This case has happened when the Track Section overview screen
only shows one TCB in the list. The procedure for this is as follows:
<ol class="enumerate1" >
<li
class="enumerate" id="x1-20x1">Go to the second TCB (the one that wasn’t recognized). It should show “End of Interlocking” on the relevant side.
</li>
<li
|
