MIDI Input with Propeller?

6581

Hi,

I found the OBJ for Midi Input at the Parallax Obex but have no
clue how to use it to handle NoteOn, NoteOff, etc.

I'd like to use NoteOn, NoteOff, Pitchbend etc. to control
things like the Stereo Spatializer, Vocal tract etc.

Any help very appreciated!

mpark

Search the forum for my "sick day synthesizer" thread. It's a very simple polyphonic and velocity-sensitive synth controlled by MIDI. It only handles NoteOns and NoteOffs but it should give you a start.

6581

mpark wrote: »

Search the forum for my "sick day synthesizer" thread. It's a very simple polyphonic and velocity-sensitive synth controlled by MIDI. It only handles NoteOns and NoteOffs but it should give you a start.

Okay, thanks!
It works. I can handle the MidiOn, MidiOff and Pitchbend events. But
the Controller Change doesn't seem to work.

The Code looks something like:

CON
    _clkmode = xtal1 + pll16x

OBJ
    [other OBJs]
    MIDI: "FullDuplexSerial"

PUB main | b, runningStatus ch1note, ch2note, ch3note, ch0bend, ch0bendval, ccnum, ccval, ch0vel, ch1vel, ch2vel
    MIDI.start(5,4,%0000,31250)
    
    repeat
        ch1note := -1
        ch2note := -1
        ch3note := -1

        if(b := MIDI.rxcheck) <> -1
            if b & $80
                runningStatus := b
                b := MIDI.rx

            if(runningStatus) == $B0    ' CC handling (broken?)
                ccnum := MIDI.rx
                ccval := MIDI.rx
                ' For some reason we must receive a 3rd dummy byte
                MIDI.rx
            if(runningStatus) == $90    ' Note on event on Midi Channel 1
                ch1note := b
                ch1vel := MIDI.rx
                if ch1vel == 0
                    ch1note := -1
            if(runningStatus) == $91    ' Note on event on Midi Channel 2
                ch2note := b
                ch2vel := MIDI.rx
                if ch1vel == 0
                    ch2note := -1
            if(runningStatus) == $92    ' Note on event on Midi Channel 3
                ch3note := b
                ch3vel := MIDI.rx
                if ch3vel == 0
                    ch3note := -1
            if(runningStatus) == $E0    ' Pitch bend event on Midi Channel 1
                ch0bend := midi.rx

        if ch0note <> -1
            (do some note on event on ch0)
        else
            (do some note off event on ch0)

        (do this for every channel)

So Midi NoteOn+NoteOff+PitchBend for channel 1, 2 and 3 works properly,
but the propeller hangs if it receives a controller change message, if not
receiving the dummy byte. Any suggestion?

Im using this as a reference: http://museinfo.sapp.org/doc/formats/midi/

Thanks

Ariba

You have received the first data byte (the controller number) already. So the code for CC should look like that:

if(runningStatus) == $B0    ' CC handling (broken?)
                ccnum := b
                ccval := MIDI.rx

Andy