clock-output.txt

$ perl6 -I. clock.pl6 
0000011011011010100010011001010100000101101001101000011011011111
0000011011011010100010011001010100001011100111000110011111011111
0000011011011010100010011001010101000001010000010101000011011111
0000011011011010100010011001010101000111001101110011000111011111
0000011011011010100010011001011101011001101100100110101011011111
0000011011011010100010011001010101000111001101110011000111011111
0000011011011010100010011001010101000001010000010101000011011111
0000011011011010100010011001010100001011100111000110011111011111
0000011011011010100010011001010100000101101001101000011011011111
0000011011011010100010011001010100001011100111000110011111011111
0000011011011010100010011001010101000001010000010101000011011111
0000011011011010100010011001010101000111001101110011000111011111
0000011011011010100010011001011101011001101100100110101011011111
0000011011011010100010011001010101000111001101110011000111011111
0000011011011010100010011001010101000001010000010101000011011111
0000011011011010100010011001010100001011100111000110011111011111
0000011011011010100010011001010100000101101001101000011011011111
0000011011011010100010011001010100001011100111000110011111011111
^C

clock.pl6

use Audio::PortMIDI;

use CircularArray;

my $pm = Audio::PortMIDI.new;
my $stream = $pm.open-output($pm.default-output-device.device-id, 32);

constant MfID = 0x7d; # Manufacturer ID 'Educational'

my $step = 1/((120/60)*2);

my CircularArray $nth;
{
    $_ = 0;
    my @sig;
    @sig.push($_++) while 0 fff 3;
    @sig.push($_--) while 4 fff 1;
    $nth .= new(storage => @sig);
}

react {
    whenever Supply.interval($step) {
        my $data = $nth[$++];

        # as per https://www.midi.org/specifications/item/table-1-summary-of-midi-message
        # 11110000 - start system exclusive
        # 01111101 - 'Educational'
        # $data    - the actual message
        # 11110111 - end sysex
        my $sysmsg = "11110000" ~ sprintf("%08b", MfID) ~ sprintf("%08b", $data) ~ "11110111";
        my $m = Audio::PortMIDI::Event.new(event => $sysmsg.Int);
        say sprintf "%064b", $m.Int;
        
        $stream.write($m);
   }    
}  

listener-output.txt

$ perl6 listener.pl6 
0000000000000000000010000111000100000000000000000110011111011111
0000000000000000000010010110110000000000000000000101000011011111
0000000000000000000010100110011100000000000000000011000111011111
0000000000000000000010110110000100000000000000000110101011011111
0000000000000000000011000101101100000000000000000011000111011111
0000000000000000000011010101010100000000000000000101000011011111
0000000000000000000011100100111100000000000000000110011111011111
# one missing here
0000000000000000000100000100010000000000000000000110011111011111
0000000000000000000100010011111100000000000000000101000011011111
0000000000000000000100100011100100000000000000000011000111011111
0000000000000000000100110011001100000000000000000110101011011111
0000000000000000000101000010110100000000000000000011000111011111
0000000000000000000101010010011100000000000000000101000011011111
0000000000000000000101100010001000000000000000000110011111011111
# same missing here
0000000000000000000110000001011000000000000000000110011111011111

listener.pl6

use Audio::PortMIDI;

my $pm = Audio::PortMIDI.new;
my $clock = $pm.open-input($pm.default-input-device.device-id, 32);

my $out = $pm.open-output($pm.default-output-device.device-id, 32);

my $code = supply {
    # not sure this is a great idea... 
    whenever supply { emit $clock.poll while True } {
        emit $clock.read(1)
    }
}

react {
    whenever $code -> $ev {
        if $ev {
            say sprintf "%064b", $ev[0].Int;
            
#           if $ev[0].data-one == 0 {
#               my $event-type = $++ %% 2 ?? NoteOn !! NoteOff;
#               my $n = Audio::PortMIDI::Event.new(:$event-type, :channel(3), data-one => 49, data-two => 127);
#               $out.write($n);
#           }
        }
    }
}

questions.txt

I'm only building an event of 32 bits. Should the event still contain 64, as it apparently does?
Where do those missing messages go..?
Is building messages and only passing :event maybe just a bad idea, because it's not really supported or is that just sysex?