[sdiy] midi to arpeggio clock

[Jason Proctor]

>Assuming that the stream doesn't contain wretched sysex data, you can
>just watch for those and ignore all else (I think.)

according to the spec, as was quoth on a recent AH thread, system 
realtime messages can occur anywhere -- even within a sysex stream. i 
was surprised.

and sysex payload must have the high bit clear, so it really is just 
a case of checking for those values. if you're only doing clock, the 
task is easy.