[sdiy] Midi problems

[Thomas Hudson]

On Wed, 2002-04-03 at 14:17, Tim Ressel wrote:
> Hey all,
> 
> After days of avoiding eye contact with the Midi2cv
> project which has been consistantly kicking my butt,
> I've dug back into it. 
> 
> Guess what? I took a look at the midi info from my
> kbd, and I seem to be getting Note On ($9x) commands
> for both key down and key up.  
> 
> Have I missed something here?
> 
Most keyboards implement note off as a note on message with
zero velocity. The reason being is that they can use running
status. Running status allows one to not resend a status byte
if the next message has the same status. So intead of a key
down and up being:

0x90 0x64 0x64 
0x80 0x64 0x0

you'll have:

0x90 0x64 0x64
0x64 0x00        <= no need to resend 0x90

A note on with velocity zero is equal to a note off.

Tomy