had enough of mac, looking for new OS and laptop

[Jay Vaughan]

>> Very weird, this really doesn't usually happen on OSX unless you've installed a ton of CrapWare.
> 
> Hmm, eagle, adium, skype, logic pro... that's about it really.
> 

No "Mac Defender"? 


>> How are you sending sysex MIDI data to the interface - using a *MIDIPacketList (full of sysex data) sent to MIDISend(), or "1-or-3 bytes at a time" in your own internal loop, also calling MIDISend()?
>> 
> 
> MIDI SYSEX librarian is the tool I'm using, I *WISH* MIDI-OX was
> available on OSX.
> 


Ah, you are not talking about code you've written, but someone elses?  Well then it points to very dodgy drivers somewhere ..

> 
> Errr no, skipping 2 bytes after receiving/sending 4... consistently..
> it smacks of a buffer problem somewhere.
> 

Yes, this is a buffer alignment issue, and I'll explain it further ..

>> Basically, if you try to send a sysex buffer byte-for-byte, it won't work due to the internals of CoreMIDI trying to keep the MIDI stream "properly byte aligned" (its needed for properly dealing with running status events and so on), but if you build up a MIDIPacketList as a sysex buffer, you *shouldn't* have any problems like you're experiencing.  Or, better yet, use MIDISendSysex .. this works flawlessly in my experience.
>> 
> 
> yeah, but this is a SYSEX send, it *SHOULD* send byte for byte what is sent!

.. MIDI messages under OSX can be sent as either the normal 3-byte type, or SYSEX dumps (variable length).  If you're sending SYSEX a byte at a time with the 3-byte message API, then there *will* be 'gaps' in the stream that OSX gets confused by.  Better to use the "SYSEX buffer" API, and not try to do it yourself a byte at a time .. 

>> Dunno if that is helping you in any way, but its quite possible that the MIDI driver you're using (what is it, by the way?) is interfering with the two different entry points into a driver for MIDI data - single-message MIDI sends, and variable-length SYSEX sending ..
>> 
> 
> I have no idea what driver, the device itself is supported by core
> audio and just appears as "MIDI Interface 1, In and Out"
> 

What device, though, that is the question .. ?



;
--
Jay Vaughan