manual/include/midi-tracer.html

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

<p>
  The <dfn>MIDI Tracer</dfn> window, which is accessed by selecting <kbd
  class="menu">Window &gt; MIDI Tracer</kbd> from the main menu, is similar to
  the <a href="@@midi-list-editor">MIDI List Editor</a> in that it displays
  MIDI information as tabular text, and has a vertical flow (i.e. the
  events follow a top to bottom time-oriented order).
</p>

<p>
  Its use is different however, as it is <em>not</em> bound to a specific
  region or track; the MIDI shown in the MIDI Tracer window is any global input
  or output Ardour presents to the system. As such, it is a very useful way to
  monitor MIDI traffic, whether it is an external controller or device or the
  input or output of any track.
</p>

<p class="note">
  The MIDI Tracer can list all types of MIDI and "audio" events, and <a href="@@midi-scene-automation">scene automation</a> and <a href="@@timecode-generators-and-slaves">timecode</a> events as well.
</p>

<p>
  The window consists 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; once this limit is
  reached, older events will be removed from the 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 <a href="@@on-clock-and-time">absolute times</a></td>
</tr>
<tr>
  <th><dfn>Decimal</dfn></th>
  <td>If checked, shows the MIDI data as decimal values instead of
  hexadecimal</td>
</tr>
<tr>
  <th><dfn>Enabled</dfn></th>
  <td>If checked, events are displayed in the events list as they occur,
  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, keeping 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, etc.)</td>
</tr>
<tr>
  <th>MIDI channel</th>
  <td>The MIDI channel the event happened in</td>
</tr>
<tr>
  <th>MIDI data bytes (event parameters)</th>
  <td>Parameters of the event, e.g. for a Note On: what the <a
  href="@@midi-notes-ref">note</a> was, and its velocity</td>
</tr>
</table>