Annoying MIDI

[Hack]

Well, I've been up all night trying to figure this one out..

It seems that when I send a MIDI message via "HEX2 MidiVAL" I get a different result than "$3C" (if the values match!) I've tried so many different ways to figure out what's going on-- and how to fix it.. but nothing works...

I am not an expert but from what I can see, it looks correct... If you hook up a MIDI output to a keyboards MIDI input, you will hear the issue I am referring to.

Code Select Expand

' {$STAMP BS2}
' {$PBASIC 2.5}


' -----[ I/O Definitions ]-------------------------------------------------
MidiOut   PIN 15

' -----[ Variables ]-------------------------------------------------------
MidiBaud  CON $8000 + 12
MIDIVAL   VAR Byte
Counter   VAR Word
' -----[ Program Code ]----------------------------------------------------

DO
Counter = Counter + 1

    SEROUT MidiOut, MidiBaud, [$96, $3C, $55, $96, HEX2 MIDIVAL, $7F]
    DEBUG HOME, "PLAYING $3C + MIDIVAL = $", HEX2 MIDIVAL, CR

    IF (Counter < 70) THEN
      IF (MIDIVAL + 1 < 61) THEN MIDIVAL = MIDIVAL + 1
        DEBUG "WHERE IS UNISON?                  "
      ELSE
        MIDIVAL = MIDIVAL + 1
        DEBUG "TRANSITION BETWEEN 9F AND A0?"
    ENDIF
    IF (MIDIVAL > 127) THEN
      Counter = 0
      MIDIVAL = 0
    ENDIF
    PAUSE 200
LOOP



I tried stripping down the code to make this as easy as possible to solve:

Code Select Expand

' {$STAMP BS2}
' {$PBASIC 2.5}


' -----[ I/O Definitions ]-------------------------------------------------
MidiOut   PIN 15

' -----[ Variables ]-------------------------------------------------------
MidiBaud  CON $8000 + 12
MIDITEST  CON 60 'BASE10 = 60, BASE16 = $3C
' -----[ Program Code ]----------------------------------------------------

DO
    SEROUT MidiOut, MidiBaud, [$96, $3C, $55, $96, HEX2 MIDITEST, $7F]
    DEBUG HOME, "PLAYING $3C + MIDITEST = $", HEX2 MIDITEST
    PAUSE 200
LOOP


Shouldn't this make sense? But it SOUNDS so wrong! I'm going crazy!!

[JonnyMac]

Keep in mind that the HEX2 modifier will convert your MIDI byte to a string of two characters -- this will throw things off. 

This article may be helpful: http://www.parallax.com/Portals/0/Downloads/docs/cols/nv/vol4/col/nv94.pdf