[comp.sys.mac.programmer] MIDI on Mac+

lippold@cerl.uiuc.edu (Lippold Haken) (06/28/90)

I am successfully using the Apple MIDI Manager and the Apple MIDI Driver
on MacII series computers and on MacSE series computers.  My program does
not work on the MacPlus.  

When I get MIDI input, my readhook routine is never called by the MIDI manager.
I set breakpoints in the Apple MIDI Driver (using Macsbug) and the breakpoint
gets triggered, but somehow the data is not making it from the Apple MIDI
Driver to the Apple MIDI Manager, or the Apple MIDI Manager is losing it and
not calling my readhook routine.

When I send MIDI output, nothing is sent to the MIDI port.  If I set a break-
point in the MIDI driver, it never gets triggered.  Often the Mac will slow
down (menus plot slowly, program executes slowly, etc) after I send MIDI 
output; I guess it might be getting lots of interrupts(?) -- but when it is in
this "slow mode" it is not getting any input from the MIDI port.

Anyone have experience with the MIDI manager on the MacPlus?  I would
appreciate any help I can get.
---
Lippold Haken
CERL Music Group
University of Illinois
l-haken@uiuc.edu