jvc-midi/msx_io_ports: Add documentation for JVC MSX MIDI interface.

Thanks go to gflorez for providing port and divider information.
3 files changed, 55 insertions(+), 1 deletions(-)

M resources/index.php
A => resources/midi/jvc-midi.php
M resources/msx_io_ports.php
M resources/index.php +2 -1
@@ 235,8 235,9 @@ information, feel free to send us an ema
       <li><a href="/resources/midi/msx-midi.php">MSX-MIDI</a> · MSX Datapack Vol. 3 Section 5, English <span class="map">MAP</span></li>
       <li><a href="/resources/midi/intel_8251.pdf">Intel 8251 UART</a> · used by MSX-MIDI</li>
       <li><a href="/resources/midi/intel_8253.pdf">Intel 8253 Timer</a> · used by MSX-MIDI</li>
-      <li><a href="/resources/midi/motorola_mc68b50.pdf">Motorola MC68B50</a> · used by Philips Music Module</li>
+      <li><a href="/resources/midi/motorola_mc68b50.pdf">Motorola MC68B50</a> · used by Philips Music Module and JVC MSX MIDI interface</li>
       <li><a href="/resources/midi/ym2148.php">Yamaha YM2148</a> · FM Sound Synthesizer Unit MIDI interface <span class="map">MAP</span></li>
+      <li><a href="/resources/midi/jvc-midi.php">JVC MSX MIDI interface</a> <span class="map">MAP</span></li>

A => resources/midi/jvc-midi.php +49 -0
@@ 0,0 1,49 @@ 
+<?php include $_SERVER['DOCUMENT_ROOT'].'/scripts/functions.php'; addHTTPHeader(); ?>
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
+  <title>JVC MSX MIDI interface</title>
+  <?php addStyles(); ?>
+<?php addHeader(); ?>
+<h1>JVC MSX MIDI interface</h1>
+<p>The JVC MSX MIDI interface is based on the <a href="motorola_mc68b50.pdf">Motorola MC6850 ACIA</a>
+with a 2 MHz clock crystal. It also provides a <a href="https://en.wikipedia.org/wiki/DIN_sync">DIN sync</a> input.
+Electro Music Research also manufactured this interface for several other platforms,
+like the <a href="https://www.worldofspectrum.org/infoseekid.cgi?id=1000830">ZX Spectrum</a>,
+<a href="http://www.cpcwiki.eu/index.php/EMR_MIDI_Interface">Amstrad CPC</a> and
+<a href="http://mdfs.net/Info/Comp/BBC/MIDI/">BBC Micro</a>.</p>
+  <th>Port</th>
+  <th>Description</th>
+  <td>#00</td>
+  <td>DIN sync input. Bit 0: stop / start, bit 1: clock pulse.</td>
+  <td>#02</td>
+  <td>MC6850 ACIA command / status. Note: use /64 divider.</td>
+  <td>#03</td>
+  <td>MC6850 ACIA data</td>
+<p>The I/O ports are mirrored at #08-#0B.</p>
+<p>Thanks go to gflorez for
+<a href="https://www.msx.org/forum/msx-talk/hardware/jvc-msx-midi-interface?page=1#comment-377145">providing</a>
+port and divider information.</p>
+<p class="signed">Grauw</p>
+<?php addFooter(); ?>

M resources/msx_io_ports.php +4 -0
@@ 32,6 32,10 @@ If you have additions or see an error, p
   <td>Sensor Kid</td>
+  <td>#00-#03</td>
+  <td><a href="/resources/midi/jvc-midi.php">JVC MSX MIDI interface</a> (MC6850, mirrored on ports #08-#0B)</td>
   <td>FAC MIDI interface (i8251, mirrored on ports #00-#07)</td>