manual/include/midi-tracer.html

<figure>
  <img src="/images/midi-tracer.png" alt="The MIDI Tracer window">
  <figcaption>
    The MIDI Tracer window
  </figcaption>
</figure>

<p>
  The <dfn>MIDI Tracer</dfn> is similar to the <a href="@@midi-list-editor">MIDI
  List Editor</a>, in the way that it displays MIDI information as a tabular text
  view, and has a vertical flow, i.e. the events follow a top to bottom time
  order.
</p>
<p>
  Its use is different though, as it is <em>not</em> bound to a specific region or track:
  the MIDI that is monitored is any global input or output Ardour presents to the
  system. It is hence a very useful option to monitor a MIDI port, be it an external
  controller/device or the in/output of any track.
</p>
<p>
  It is accessed by selecting the <kbd class="menu">Window &gt; MIDI Tracer</kbd>
  menu.
</p>
<p>
  The window is made of:
</p>
<table class="dl">
  <tr><th><dfn>Port</dfn></th><td>a list of all the MIDI ports Ardour presents to the system. They
    are both internal and external and are the same ports Ardour presents to JACK, if
    enabled.</td></tr>
  <tr><th>the events list</th><td>where all the events for this port are listed, see below</td></tr>
  <tr><th><dfn>Line history</dfn></th><td>how many lines should be kept in the events list</td></tr>
  <tr><th><dfn>Delta times</dfn></th><td>if checked, shows the times as the duration since the last event, instead of the <a href="@@on-clock-and-time">absolute time</a></td></tr>
  <tr><th><dfn>Decimal</dfn></th><td>if checked, shows the MIDI data as decimal values instead of the original hexadecimal values</td></tr>
  <tr><th><dfn>Enabled</dfn></th><td>if checked, the events are displayed in the events list, otherwise stops the logging</td></tr>
  <tr><th><dfn>Auto-Scroll</dfn></th><td>if checked, the events list scrolls as new events are logged, allowing to keep the newest events on screen</td></tr>
</table>

<p>
  The events list displays the events as columns:
</p>
<table class="dl">
  <tr><th>time of the event</th><td>either absolute or relative, based on the <kbd class="option">Delta times</kbd> checkbox</td></tr>
  <tr><th>MIDI status (event type)</th><td>what midi events happened (e.g. Note On, Note Off, Pitch Bend, &hellip;)</td></tr>
  <tr><th>MIDI channel</th><td>in which MIDI channel did the event happen</td></tr>
  <tr><th>MIDI data bytes (event parameters)</th><td>parameters of the event, e.g. for a Note On: what <a gref="@@midi-notes-ref">note</a> was it, and which was the note's velocity</td></tr>
</table>

<p class="note">
  Note: The MIDI Tracer can lists all kind of MIDI events, "audio" ones, but also <a href="@@midi-scene-automation">scene automation</a> or <a href="@@timecode-generators-and-slaves">timecodes</a> ones.
</p>