That's took me back to when I wrote a complete MIDI tracker program for the Atari ST based on the popular tracker program at the time. I'm assuming MIDI these days is via the USB!?!? Not sure though.
I think the most important piece that I added to my tracker was the SysEx dump functions which helped when setting up more than one MIDI instrument. I had three keyboards at the time and one was fantastic for drum sounds. And I got it so you could free hand draw volume levels over a particular track. If you get a project started on this then I'd be interested to see how you get on.
Must be getting old, I'm reminiscing again...
Mental arithmetic? Me? (That's for computers) I can't subtract a fart from a plate of beans!
Warning! May contain Nuts!