primus has asked for the wisdom of the Perl Monks concerning the following question:

hail monks,

well, i must say, you monks were so much help on my last post, i must tap some more of this bottomless knowledge...

OK, i am playing around with the Win32::MIDI module ( on a win32 machine ) and i wanted to know if it were possible to play a chord with this module? basically a snippet of the example is as follows: 
my $midi_obj = Win32::MIDI->new();

    # print number of available (writing) devices
    
print $midi_obj->numDevices() . "\n";

    # open a device

$midi_obj->openDevice(0);

    # set default channel

$midi_obj->cur_channel(1);

    # play a note by absolute value (numeric)
    # middle C - 60
    # note,dur,velocity
    
$midi_obj->play_note(60,2.5,127) || print $midi_obj->error() . "\n" an
+d $midi_obj->reset_error();

[download]


there are some neat things you can do with this module, but i couldnt seem to find anything on playing chords... i was thinking maybe if you had two channels open each note would play on the each channel simultaneously, but that did not work... i dont know if this module is just not built to play chords, or what? but if you monks can suggest another module that can be used on win32 for chords, i would be much obliged.

thanks alot for the help!

Replies are listed 'Best First'.
Re: playing chords with MIDI modules...
by Mr. Muskrat (Canon) on Jan 20, 2003 at 19:30 UTC

    I got it to play a chord! It's not pretty, nor is it optimized. It is fairly easy to understand though. 

    use Win32::MIDI;
my $midi_obj = Win32::MIDI->new();
$midi_obj->openDevice(0);

indiv(1, 3); # 1 second duration, start at middle C
chord(3, 3); # 3 second duration, same chord

sleep(1);
$midi_obj->closeDevice();

# play_note(NOTE, DURATION, VELOCITY, CHANNEL, ON/OFF, OCTAVE)

sub indiv {
  my $duration = shift;
  my $octave = shift;
  
  # play each note individually
  $midi_obj->play_note('C', $duration, 127, 1, 1, $octave)
   || print $midi_obj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('E', $duration, 127, 1, 1, $octave)
   || print $midi_obj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('G', $duration, 127, 1, 1, $octave)
   || print $midi_obj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('C', $duration, 127, 1, 1, $octave+1)
   || print $midi_obj->error() . "\n" and $midi_obj->reset_error();
}


sub chord {
  # get the duration to play the C chord
  my $duration = shift;
  # get the octave to play the C chord at
  my $octave = shift;
  
  # play the chord
  $midi_obj->play_note('C', $duration, 127, 1, 0, $octave)
   || print $midi_obj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('E', $duration, 127, 1, 0, $octave)
   || print $midi_obj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('G', $duration, 127, 1, 0, $octave)
   || print $midi_obj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('C', $duration, 127, 1, 1, $octave+1)
   || print $midi_obj->error() . "\n" and $midi_obj->reset_error();
}

    [download]

    Updated: Moved the individual notes into a different subroutine. Changed ON/OFF flag for final note of chord to 1. Added duration parameter to both subroutines.

[reply]
[d/l]
      Addon to Mr. Muskrat's code: 
      
mary(3);

sub mary {
  my $octave = shift;
  
  $midi_obj->play_note('E', ".5", 127, 1, 1, $octave) || print $midi_o
+bj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('D', ".25", 127, 1, 1, $octave) || print $midi_
+obj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('C', ".5", 127, 1, 1, $octave) || print $midi_o
+bj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('D', ".5", 127, 1, 1, $octave) || print $midi_o
+bj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('E', ".5", 127, 1, 1, $octave) || print $midi_o
+bj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('E', ".5", 127, 1, 1, $octave) || print $midi_o
+bj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('E', ".75", 127, 1, 1, $octave) || print $midi_
+obj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('D', ".5", 127, 1, 1, $octave) || print $midi_o
+bj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('D', ".5", 127, 1, 1, $octave) || print $midi_o
+bj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('D', ".5", 127, 1, 1, $octave) || print $midi_o
+bj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('E', ".5", 127, 1, 1, $octave) || print $midi_o
+bj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('G', ".5", 127, 1, 1, $octave) || print $midi_o
+bj->error() . "\n" and $midi_obj->reset_error();
  $midi_obj->play_note('G', ".5", 127, 1, 1, $octave) || print $midi_o
+bj->error() . "\n" and $midi_obj->reset_error();
}

      [download]
      Guess this tune...

      -----------------------
      Billy S.
      Slinar Hardtail - Hand of Dane
      Datal Ephialtes - Guildless
      RallosZek.Net Admin/WebMaster

      perl -e '$cat = "cat"; if ($cat =~ /\143\x61\x74/) { print "Its a cat!
+\n"; } else { print "Thats a dog\n"; } print "\n";'

      [download]
[reply]
[d/l]
[select]
        Name this tune: 
        
song(3);

sub song {
  my $octave = shift;

  my $num = 0;  

  while ($num < 10) {
      $midi_obj->play_note('E', "1.25", 127, 1, 1, $octave) || print $
+midi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('G', ".5", 127, 1, 1, $octave) || print $mi
+di_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('G#', ".25", 127, 1, 1, $octave) || print $
+midi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('B', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('E', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('D', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('D', "1", 127, 1, 1, $octave) || print $mid
+i_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('B', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('F#', ".25", 127, 1, 1, $octave) || print $
+midi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('F', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('B', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('D', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('E', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
    $num++;
  }
}

        [download]
        Send me a message to see if your right...

        -----------------------
        Billy S.
        Slinar Hardtail - Hand of Dane
        Datal Ephialtes - Guildless
        RallosZek.Net Admin/WebMaster

        perl -e '$cat = "cat"; if ($cat =~ /\143\x61\x74/) { print "Its a cat!
+\n"; } else { print "Thats a dog\n"; } print "\n";'

        [download]
[reply]
[d/l]
[select]
      Guess this song... 
      song2(3);

sub song2 {
  my $octave = shift;

  my $num = 0;  

  while ($num < 10) {
      sleep(.5);
      $midi_obj->play_note('D', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('F', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('D', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('G', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('D', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('F', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      $midi_obj->play_note('D', ".25", 127, 1, 1, $octave) || print $m
+idi_obj->error() . "\n" and $midi_obj->reset_error();
      sleep(2);
    $num++;
  }
}

      [download]
      Send message to get answer...

      -----------------------
      Billy S.
      Slinar Hardtail - Hand of Dane
      Datal Ephialtes - Guildless
      RallosZek.Net Admin/WebMaster

      perl -e '$cat = "cat"; if ($cat =~ /\143\x61\x74/) { print "Its a cat!
+\n"; } else { print "Thats a dog\n"; } print "\n";'

      [download]
[reply]
[d/l]
[select]
Re: playing chords with MIDI modules...
by Mr. Muskrat (Canon) on Jan 07, 2003 at 15:55 UTC

    I attempted to do it using the low level method and sending notes to three different channels without success but I'm no MIDI expert.

    use Win32::MIDI;
my $midi_obj = Win32::MIDI->new();
$midi_obj->openDevice(0);
## Low-Level Method -- Writing Directly To The Device,
## Creating Your Own MIDI Messages
my @on = ("\x00\127\127\x90","\x00\127\160\x91","\x00\127\090\x92");  
+  
my @off  = ("\x00\127\127\x80","\x00\127\160\x81","\x00\127\090\x82");
for (@on) { $midi_obj->writeMIDI(unpack("N",$_)); }
sleep(3);
for (@ff) { $midi_obj->writeMIDI(unpack("N",$_)); }

    [download]

    Perhaps you should contact the author and see if he can help.

[reply]
[d/l]
      thanks for the attempt, i think i will just email the creator...
[reply]
Re: playing chords with MIDI modules...
by Mr. Muskrat (Canon) on Jan 07, 2003 at 23:55 UTC

    Win32::MIDI::API looks very interesting too.

    I think I'll wait until the author releases it for AS Perl though... (Which is mentioned in the Todo section of the POD.)

[reply]
Re: playing chords with MIDI modules...
by primus (Scribe) on Jan 07, 2003 at 04:15 UTC
    well... i guess this cant be done, should i email the guy who wrote Win32::MIDI?
[reply]

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